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Atmospheric pollution is a critical issue in public health systems. The simulation of atmospheric pollution dispersion in urban blocks, using CFD, faces several challenges, including the complexity and inefficiency of existing CFD software, time-consuming construction of CFD urban block geometry, and limited visualization and analysis capabilities of simulation outputs. To address these challenges, we have developed a prototype system that couples 3DGIS and CFD for simulating, visualizing, and analyzing atmospheric pollution dispersion. Specifically, a parallel algorithm for coordinate transformation was designed, and the relevant commands were encapsulated to automate the construction of geometry and meshing required for CFD simulations of urban blocks. Additionally, the Fluent-based command flow was parameterized and encapsulated, enabling the automatic generation of model calculation command flow files to simulate atmospheric pollution dispersion. Moreover, multi-angle spatial partitioning and spatiotemporal multidimensional visualization analysis were introduced to achieve an intuitive expression and analysis of CFD simulation results. The result shows that the constructed geometry is correct, and the mesh quality meets requirements with all values above 0.45. CPU and GPU parallel algorithms are 13.3× and 25× faster than serial. Furthermore, our case study demonstrates the developed system's effectiveness in simulating, visualizing, and analyzing atmospheric pollution dispersion in urban blocks. [ABSTRACT FROM AUTHOR]

Atmospheric pollution is a critical issue in public health systems. The simulation of atmospheric pollution dispersion in urban blocks, using CFD, faces several challenges, including the complexity and inefficiency of existing CFD software, time-consuming construction of CFD urban block geometry, and limited visualization and analysis capabilities of simulation outputs. To address these challenges, we have developed a prototype system that couples 3DGIS and CFD for simulating, visualizing, and analyzing atmospheric pollution dispersion. Specifically, a parallel algorithm for coordinate transformation was designed, and the relevant commands were encapsulated to automate the construction of geometry and meshing required for CFD simulations of urban blocks. Additionally, the Fluent-based command flow was parameterized and encapsulated, enabling the automatic generation of model calculation command flow files to simulate atmospheric pollution dispersion. Moreover, multi-angle spatial partitioning and spatiotemporal multidimensional visualization analysis were introduced to achieve an intuitive expression and analysis of CFD simulation results. The result shows that the constructed geometry is correct, and the mesh quality meets requirements with all values above 0.45. CPU and GPU parallel algorithms are 13.3× and 25× faster than serial. Furthermore, our case study demonstrates the developed system’s effectiveness in simulating, visualizing, and analyzing atmospheric pollution dispersion in urban blocks.

By establishing a distributed high complexity C/S architecture, coding CAD/GIS plug-in to achieve the export function, and based on the interactive visualization platform of 3D spatial data, 3DGIS platform was developed, and the virtual mine simulation platform was built by combining VR technology. The results show that the virtual mine simulation system can classify the internal operation program, separate the external display operation from the internal logic operation, and the system operation delay is low, efficient and stable. The system has a strong vertical transfixtion ability of spatial data and realizes the integration of different dimensional data. The system has unique advantages in dynamic visualization of mine objects. On the basis of restoring various physical and geographic information of mines, it can be independently set and select the information of simulated scenes.

The similarities and differences between industry foundation classes (IFC) and city geography markup Language (CityGML) are analyzed in terms of geometric expression and semantic information. A transformation method between IFC and CityGML for utility tunnel is established including semantic extraction, geometry and coordinate system transformation. Then the transformation experiment of utility tunnel in Liupanshui city is carried out and the results show that the mapping rules of the IFC utility tunnel model and the CityGML utility tunnel model can realize the transformation of the IFC utility tunnel model to the CityGML model, at the same time, the converted CityGML utility tunnel model contains the property information extracted by the IFC model, which can be used for the integration of three dimension geographical information system (3DGIS) and building information modeling (BIM), it helps to promote the life cycle management of urban underground utility tunnels. [ABSTRACT FROM AUTHOR]

In cities, the main source of air pollutants is vehicle exhaust. It has become an urgent problem for many cities to explore the law of vehicle exhaust diffusion and actively seek for improvement measures. At present, there are many researches on the simulation of vehicle exhaust diffusion, but few on the modeling of diffusion process and volume visualization analysis. This paper integrates California line source dispersion model‐4(CALINE4) model and 3DGIS to solve the problem of urban vehicle exhaust diffusion simulation and dynamic visualization. Firstly, a street‐scale framework of vehicle exhaust diffusion simulation and visualization is established, and a continuous concentration field is established to express the diffusion processing. A unified data model is used in the semantic space to integrate the data of buildings, roads, trees and dynamic diffusion process data. Secondly, a graphics processing unit ‐ based direct volume rendering method is used to visualize the dynamic diffusion data, and this algorithm is improved in real‐time gradient calculation, texture sampling and time‐based interpolation. Finally, this paper analyzes the vehicle exhaust diffusion of a road in the central business district area of Beijing. The experimental results show that the coupling application of 3DGIS and CALINE4 model can better reveal the spatial and temporal distribution characteristics of urban vehicle exhaust and concentration, which verifies the reliabless and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

A display implementation method of coal mine business data based on 3DGIS was put forward. The method adopts way of data center to manage basic spatial data and business system data. Combining with 2DGIS and 3DGIS, it can comprehensively and intuitively show coal mine business data taking desktop platform and Web platform as the carrier. The method not only can provide intuitive and efficient way of data acquisition and perception for coal users, but also can provide functions of efficient space analysis and hidden information mining.

A single architecture cannot meet the demand for the development of an emergency early warning auxiliary decision system.In order to solve this problem,a microservice architecture is introduced to design and develop the system.By analyzing the advantages of applying a microservice architecture in a complex systeminstead of a traditional monomer-type structure,we designed a microservice architecture based on the emergency early warning information release auxiliary decision system. This system selects the Spring Cloud service framework, and makes an appropriate extension on itto create the registry and gateway based on the system design.The system adopts a 2D and 3D integrated geographic information system as the display platform.By accessing the static monitoring data and hazard source dymamic monitoring data on various industries, the system can integrate and processes data according to the set mode,and assists in command and decision-making in the early warning information generation,release,and emergency response stages.This design scheme lias been applied tothe Hubei province emergency early warning and release aided decision system.The rationality and effectiveness of this kind of system,which uses a microservice architecture, has been verified. [ABSTRACT FROM AUTHOR]

3D Geographic Information Systems (3D GIS) are systems that are capable of making spatial analyses that consider the tridimentional and semantic representation of objects. These systems make these analyses through its planialtimetric coordinates. The City Geography Markup Language (CityGML) is used for the representation of cities and urban applications. The CityGML is an international standardized data model based on XML used to store and exchange information through 3D representation of cities. This standardized data model has 5 Levels of Detail - LOD, varying from LOD 0 (least detailed) to 4 (most detailed). The main challenges for the implementation of these systems refer to the techniques used for obtaining data and the data format, and also all the software used in the geometric modeling of the urban model. The data related to the buildings were manipulated with the QGIS software in this study. This made it possible to obtain the height of the buildings by the elevation difference between the Digital Surface Model and the Digital Terrain Model. This paper presents and discusses the first results of the geometric modeling made in the campus of the Federal University of Bahia (UFBA), by using airborne laser scanning data, integrating QGIS, Rhinoceros and CityGML. [ABSTRACT FROM AUTHOR]

The seismic characterization of buildings plays a fundamental role in Portugal since a considerable percentage of the building stock is vulnerable to this phenomenon. It provides reasonable measures which helps to minimize and mitigate the consequences of an eventual seismic event. The paper presents a 3DGIS-based methodology to assess the building seismic vulnerability, based on geometric, structural and material properties for each building, with a focus on the Pombalino buildings. For that purpose, in the first step the data provided by national institutions were organized and stored in a GIS database and applied to build the 3D model, in a procedural modelling approach, and then a simplified seismic risk evaluation methodology was developed and applied to the heritage Lisbon city centre. The followed methodology proved to be very efficient at an urban scale, allowing an easy identification of the vulnerable buildings and the viewing of the surrounding geometries, assisting the interpretation of their spatial distribution. A more detailed study will imply the in situ data collection to calibrate the estimative of fundamental period and to identify structural changes against the officially registered, which are crucial to develop the real assessment of the seismic vulnerability. [ABSTRACT FROM AUTHOR]

Aiming at the demands of quick visualization and dynamic information management of large-scale wind farm, a Skyline-based method was proposed for dynamically constructing three-dimensional scenes of wind turbine generator system(WTGS). The proposed method firstly utilized Terra Builder software to generate 3D basic terrain scenes for Wind Farm. Then 3D refined models of tower, nacelle and wind turbine rotor were unifiedly built by Skech Up tools, respectively. Finally, the 3D model of wind farm was dynamically constructed by combining three 3D refined models according to the associated position and attribute information. The results indicate that our method can rapidly realize 3D representation and dynamic simulation of wind turbine generators. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The visualization of the traditional 3DGIS is relatively backward and difficult to meet the needs of some practical applications. To improve the simulation fidelity of 3DGIS, we apply the most popular deferred shading technology to the 3DGIS and combine with the physical BRDF illumination model, SSAO and HDR technology, to propose a new 3DGIS rendering method (named as BSHRF). The physical BRDF illumination model improves the material effect of 3DGIS. The SSAO technology improves the light details of scene reality using cheap computing; the HDR technology raises the image fidelity one level again. Finally, to validate the proposed method is feasible and advanced, the vegetation scene and 3D building scene are rendered respectively using the BSHRF method in a 3DGIS software platform Gaea explorer, and the BSHRF method is compared with the current popular 3DGIS software Google Earth and ArcScene from two aspects of the rendering quality and efficiency. The results show that the BSHRF method can get a better rendering fidelity under the condition of no loss of rendering efficiency. [ABSTRACT FROM AUTHOR]

Raffaello Sanzio intuì per primo che il mondo antico, come lo vedevano i suoi occhi, non era che l’eco sbiadita di quella ricchezza che pur doveva caratterizzarne l’esperienza artistica. Oggi la tecnologia permette di realizzare il sogno di Raffaello e di restituire le immagini delle antiche architetture, rivoluzionando la percezione del patrimonio culturale da parte del pubblico moderno. La nostra esperienza decennale nel settore della comunicazione del bene culturale ha consentito di confrontarci con diversi casi: dalla Domus Aurea, all'Ara Pacis; dai filmati divulgativi agli applicativi pensati per le postazioni fisse dei musei, fino alla creazione di software per la gestione dei dati degli scavi archeologici. Sempre ponendo al centro di ogni lavoro i cardini del nostro modo di fare ricerca: l'attenzione al linguaggio, quale strumento di comprensione estetica, e la gestione informatizzata delle fonti, come apparato di studio e metodo di validazione scientifica delle ricostruzioni.[L’impostazione del saggio è comune ai due autori. In particolare, però, Stefano Borghini ha curato il paragrafo “Considerazioni generali”, mentre Raffaele Carlani “Alcune esperienze”].

It was an extremely important part of the forecast analysis of the city buildings seismic capacity for modern city earthquake prevention. Now Three-dimensional (3D) Geographic Information System (GIS) had more and more applications for its powerful display space in city earthquake prevention and disaster reduction. The paper researched the seismic intensity attenuation method and the damage factor method of city group buildings collapsed based on the SuperMap Object. Net 6R Three-dimensional component GIS platform. Combined with GIS spatial database and 3d modeling technique and Visual Studio C# 2010 development environment, it realized the Simulation of 3D seismic damage prediction under given conditions. [ABSTRACT FROM AUTHOR]

The current two causes of poor train quality of coal special operators were analyzed. It was indicated that the main cause of ineffective training of coal special operators was backwardness of training means. The defect of training and teaching software which was developed with traditional virtual reality technology was analyzed. The characteristics of virtual reality technology development platform based on three-dimensional geographic information system were introduced. The advantages of training software for special operators based on 3DGIS were analyzed. A new idea to improve the quality of safety training for coal special operators was provided by the virtual reality teaching means.

Point-based and object-based building extractions were conducted in airborne LiDAR data in a sample area of Buffalo, New York. First, the earth surface points were filtered from the entire laser scan data set using a new filtering algorithm, which combines the TIN slope modelling and statistical analysis. The off-ground points were extracted for buildings in the study area using both point cluster analysis and object-oriented classifications. The accuracies of both approaches were tested using the digitised ground truth. The outcomes of accuracy testing of the point-based method are correctness: 88.74%, completeness: 92.67% and quality: 83.50%. The results of the accuracy of object-based building extraction are correctness: 87.21%, completeness: 60.14%, and quality: 55.26%. Reconstructions of 3D building models based on the extracted building points were performed. This study contributes scientific and technological knowledge for researchers in developing more effective methods in converting the LiDAR survey to a 3D GIS database. [ABSTRACT FROM PUBLISHER]

Abstract: The GIS 3D modelling and its topology relationship are introduced and which is used into describe space topology of tunnel in mine ventilation sytem. Based on mathematical modeling and data structure, 3D visualized modeling and airflow simulation of mine ventilation system are realized with OpenGL. Further more some algorithms and key technologies used in prototype systems are profiled. This study has a great significance in increasing performance of mine ventilation management and enjoys a bright prospect for future applications. [Copyright &y& Elsevier]

Labeling plays an important role in map production, attaching specific texts to related geographic elements to provide clear environmental references. In three-dimensional geographical information systems (3DGISs), however, cluttering happens fairly commonly because of the unexpected overlapping and occlusion among labels and related objects, and results in an ambiguous and obscure environment. It generally also takes large computing power and memory to visualize spatial entities. Aimed at both unambiguous and efficient 3D map display, this article proposes an adaptive multi-resolution labeling method to deal with point, polyline, and polygon features labeling in a 3D landscape. It implements adaptive placement and view-driven label filtering without obscuring other visual features. The experiments indicated that the display of overlapping labels and label popping are reduced significantly with less computation burden while retaining the rendering quality. [ABSTRACT FROM AUTHOR]

On the study of the basic characteristics of geological objects and the special requirement for computing 3D geological model, this paper gives an object-oriented 3D topologic data model. In this model, the geological objects are divided into four object classes: point, line, area and volume. The volume class is further divided into four subclasses: the composite volume, the complex volume, the simple volume and the component. Twelve kinds of topological relations and the related data structures are designed for the geological objects. [ABSTRACT FROM AUTHOR]

On the basis of the study on road elements and the existing three-dimensional road data models, this paper puts forward the transect-based road modeling, resolves the modeling of the simplest road with two road transects, and fulfils the visualization of the road. OpenGL is applied as the tool of visualization. The map texture technology, LOD algorithm and dynamic multi-differentiating texture technology are of benefit to the construction of 3D road GIS, and improve the speed of roaming and effective visualization. This paper also disusses the combination of 2D digitall road map and 3D road scene, and the dynamic response between them. Finally, on the basis of the research on the transect-based road model, this paper develops the three-dimensional road geographic information system called virtual road (VRoad), which not only supplies road designers with a set of tool which can turn the designed 2D road data into 3D road and the high road assistant function area in computer, but also supplies the road management with a set of tool which can realize the road real time and interactive roaming, high-efficiency management. [ABSTRACT FROM AUTHOR]