scholarly journals COMPUTING WATERTIGHT VOLUMETRIC MODELS FROM BOUNDARY REPRESENTATIONS TO ENSURE CONSISTENT TOPOLOGICAL OPERATIONS

2021 ◽  
Vol VIII-4/W2-2021 ◽  
pp. 21-28
Author(s):  
M. W. Jahn ◽  
P. E. Bradley
Keyword(s):  
Graph Model ◽  
3D Models ◽  
Double Precision ◽  
Data Set ◽  
Information Models ◽  
Volumetric Models ◽  
Double Precision Arithmetic ◽  
Boundary Representations ◽  
Definition Of ◽  
Spatial Entities

Abstract. To simulate environmental processes, noise, flooding in cities as well as the behaviour of buildings and infrastructure, ‘watertight’ volumetric models are a measuring prerequisite. They ensure topologically consistent 3D models and allow the definition of proper topological operations. However, in many existing city or other geo-information models, topologically unchecked boundary representations are used to store spatial entities. In order to obtain consistent topological models, including their ‘fillings’, in this paper, a triangulation combined with overlay and path-finding methods is presented by climbing up the dimension, beginning with the wireframe model. The algorithms developed for this task are presented, whereby using the philosophy of graph databases and the Property Graph Model. Examples to illustrate the algorithms are given, and experiments are performed on a data-set from Erfurt, Thuringia (Germany), providing complex geometries of buildings. The heavy influence of double precision arithmetic on the results, in particular the positional and angular precision, is discussed in the end.

Random graphs

2018 ◽  
Author(s):  
Mark Newman
Keyword(s):  
Random Graph ◽  
Random Graphs ◽  
Large Scale ◽  
Random Network ◽  
Graph Model ◽  
Clustering Coefficient ◽  
Giant Component ◽  
Random Graph Model ◽  
Definition Of ◽  
Average Size

An introduction to the mathematics of the Poisson random graph, the simplest model of a random network. The chapter starts with a definition of the model, followed by derivations of basic properties like the mean degree, degree distribution, and clustering coefficient. This is followed with a detailed derivation of the large-scale structural properties of random graphs, including the position of the phase transition at which a giant component appears, the size of the giant component, the average size of the small components, and the expected diameter of the network. The chapter ends with a discussion of some of the shortcomings of the random graph model.

scholarly journals Has the Credibility of the Social Sciences Been Credibly Destroyed? Reanalyzing the “Many Analysts, One Data Set” Project

2021 ◽  
Vol 7 ◽  
pp. 237802312110244
Author(s):  
Katrin Auspurg ◽  
Josef Brüderl
Keyword(s):  
Social Sciences ◽  
Causal Reasoning ◽  
Research Question ◽  
Social Science Research ◽  
Science Research ◽  
Skin Tone ◽  
Data Set ◽  
The Social ◽  
The Many ◽  
Definition Of

In 2018, Silberzahn, Uhlmann, Nosek, and colleagues published an article in which 29 teams analyzed the same research question with the same data: Are soccer referees more likely to give red cards to players with dark skin tone than light skin tone? The results obtained by the teams differed extensively. Many concluded from this widely noted exercise that the social sciences are not rigorous enough to provide definitive answers. In this article, we investigate why results diverged so much. We argue that the main reason was an unclear research question: Teams differed in their interpretation of the research question and therefore used diverse research designs and model specifications. We show by reanalyzing the data that with a clear research question, a precise definition of the parameter of interest, and theory-guided causal reasoning, results vary only within a narrow range. The broad conclusion of our reanalysis is that social science research needs to be more precise in its “estimands” to become credible.

scholarly journals Formative and Summative Validation of Building Information Model-Based Cadastral Data

Land ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 822
Author(s):  
Ali Asghari ◽  
Mohsen Kalantari ◽  
Abbas Rajabifard
Keyword(s):  
Integrated Management ◽  
Summative Assessment ◽  
3D Models ◽  
Legal Aspects ◽  
Data Validation ◽  
Data Generation ◽  
Study Approach ◽  
Spatial Consistency ◽  
Information Models ◽  
Building Information

Among 3D models, Building Information Models (BIM) can potentially support the integrated management of buildings’ physical and legal aspects in cadastres. However, there is not a systematic approach to author the cadastral information into the BIM models. Moreover, the common approaches for data validation only check the final cadastral output, and they ignore the data generation steps as potential avenues for validation. Therefore, this study aims to develop the criteria and standards to check the spatial consistency and integrity of BIM-based cadastral data in the process of generating the data. The paper utilises a case study approach as its methodology to investigate the requirements of generating a BIM-based cadastral model and identify the issues within the process. The results include a formative assessment (i.e., multistep validation approach during the data generation) alongside a summative assessment (i.e., one-step validation approach at the end of data generation). This study found the summative assessment alone insufficient for 3D cadastral data validation. The paper concludes that a formative and summative assessment together can improve the validity of the data. The results will potentially bring more efficiency to modern land administration processes by avoiding the accumulation of errors in 3D cadastral data generation.

scholarly journals FINE REGISTRATION OF KILO-STATION NETWORKS - A MODERN PROCEDURE FOR TERRESTRIAL LASER SCANNING DATA SETS

2016 ◽  
Vol XLI-B5 ◽  
pp. 485-492
Author(s):  
J.-F. Hullo
Keyword(s):  
Laser Scanning ◽  
Laser Scanner ◽  
Data Sets ◽  
Data Set ◽  
Information Models ◽  
3D Network ◽  
Laser Scanners ◽  
Building Information ◽  
Set Up ◽  
Fine Registration

We propose a complete methodology for the fine registration and referencing of kilo-station networks of terrestrial laser scanner data currently used for many valuable purposes such as 3D as-built reconstruction of Building Information Models (BIM) or industrial asbuilt mock-ups. This comprehensive target-based process aims to achieve the global tolerance below a few centimetres across a 3D network including more than 1,000 laser stations spread over 10 floors. This procedure is particularly valuable for 3D networks of indoor congested environments. In situ, the use of terrestrial laser scanners, the layout of the targets and the set-up of a topographic control network should comply with the expert methods specific to surveyors. Using parametric and reduced Gauss-Helmert models, the network is expressed as a set of functional constraints with a related stochastic model. During the post-processing phase inspired by geodesy methods, a robust cost function is minimised. At the scale of such a data set, the complexity of the 3D network is beyond comprehension. The surveyor, even an expert, must be supported, in his analysis, by digital and visual indicators. In addition to the standard indicators used for the adjustment methods, including Baarda’s reliability, we introduce spectral analysis tools of graph theory for identifying different types of errors or a lack of robustness of the system as well as <i>in fine</i> documenting the quality of the registration.

scholarly journals Architecture of solution for panoramic image blurring in GIS project application

2021 ◽  
Vol 10 (2) ◽  
pp. 287-296
Author(s):  
Dejan Vasić ◽  
Marina Davidović ◽  
Ivan Radosavljević ◽  
Đorđe Obradović
Keyword(s):  
Laser Scanning ◽  
Personal Information ◽  
Point Clouds ◽  
Search Space ◽  
Legal Framework ◽  
The European Union ◽  
Data Set ◽  
General Data Protection Regulation ◽  
Panoramic Images ◽  
Spatial Entities

Abstract. Panoramic images captured using laser scanning technologies, which principally produce point clouds, are readily applicable in colorization of point cloud, detailed visual inspection, road defect detection, spatial entities extraction, diverse map creation, etc. This paper underlines the importance of images in modern surveying technologies and different GIS projects at the same time having regard to their anonymization in accordance with law. The General Data Protection Regulation (GDPR) is a legal framework that sets guidelines for the collection and processing of personal information from individuals who live in the European Union (EU). Namely, it is a legislative requirement that faces of persons and license plates of vehicles in the collected data are blurred. The objective of this paper is to present a novel architecture of the solution for a particular object blurring. The architecture is designed as a pipeline of object detection algorithms that progressively narrows the search space until it detects the objects to be blurred. The methodology was tested on four data sets counting 5000, 10 000, 15 000 and 20 000 panoramic images. The percentage of accuracy, i.e., successfully detected and blurred objects of interest, was higher than 97 % for each data set. Additionally, our aim was to achieve efficiency and broad use.

scholarly journals INVESTIGATING INTEROPERABILITY CAPABILITIES BETWEEN IFC AND CITYGML LOD 4 – RETAINING SEMANTIC INFORMATION

2018 ◽  
Vol XLII-4/W10 ◽  
pp. 33-40 ◽  
Author(s):  
G. S. Floros ◽  
C. Ellul ◽  
E. Dimopoulou
Keyword(s):  
Semantic Information ◽  
Open Data ◽  
3D Models ◽  
Solar Panels ◽  
3D City Models ◽  
Information Models ◽  
Building Information ◽  
Consistent Manner ◽  
3D Information ◽  
City Models

<p><strong>Abstract.</strong> Applications of 3D City Models range from assessing the potential output of solar panels across a city to determining the best location for 5G mobile phone masts. While in the past these models were not readily available, the rapid increase of available data from sources such as Open Data (e.g. OpenStreetMap), National Mapping and Cadastral Agencies and increasingly Building Information Models facilitates the implementation of increasingly detailed 3D Models. However, these sources also generate integration challenges relating to heterogeneity, storage and efficient management and visualization. CityGML and IFC (Industry Foundation Classes) are two standards that serve different application domains (GIS and BIM) and are commonly used to store and share 3D information. The ability to convert data from IFC to CityGML in a consistent manner could generate 3D City Models able to represent an entire city, but that also include detailed geometric and semantic information regarding its elements. However, CityGML and IFC present major differences in their schemas, rendering interoperability a challenging task, particularly when details of a building’s internal structure are considered (Level of Detail 4 in CityGML). The aim of this paper is to investigate interoperability options between the aforementioned standards, by converting IFC models to CityGML LoD 4 Models. The CityGML Models are then semantically enriched and the proposed methodology is assessed in terms of model’s geometric validity and capability to preserve semantics.</p>

scholarly journals Resource justification of the financial security of Russian industrial organizations

2020 ◽  
Vol 8 (3) ◽  
pp. 21-25
Author(s):  
Oksana Ivanova
Keyword(s):  
Industrial Production ◽  
Financial Stability ◽  
Financial Risk ◽  
Economic Security ◽  
Financial Security ◽  
Data Set ◽  
Current Time ◽  
Industrial Organizations ◽  
Definition Of ◽  
Integral Assessment

One of the components of the positions of strengthening the competitiveness and financial independence of Russian industrial organizations is the definition of interrelated compositions in the context of the national and economic security of the country. Verification of the information flow of a data set is to a large extent a tool base for determining key facts in the event of challenges and threats. Therefore, the main goal of the work is to build an information base and mathematically determine the relationship between individual indicators to establish the level of financial security of Russian industrial production. Dialectical research methods determine the fundamental foundations of the issue being disclosed. The proposed methodology for the integral assessment of financial security reflects individual positions in the system of assessing financial risk and combines both positive and negative features of the development of industrial production. As a result of the multi-criteria assessment and the calculated integral indicator, the article singles out groups for assessing the financial risk of industrial organizations, which is the basis for assessing the competitiveness and financial stability both at the current time and in the forecast future.

Sustainable urban land use: Definition, theoretical basis and review of morphology aspect concepts

2009 ◽  
Vol 1 (2) ◽  
pp. 153-170
Author(s):  
Ranka Gajić
Keyword(s):  
Land Use ◽  
Theoretical Basis ◽  
Urban Land ◽  
Urban Land Use ◽  
Point Of View ◽  
Theory And Practice ◽  
Urban Planner ◽  
Starting Point ◽  
Definition Of ◽  
Spatial Entities

The topic of sustainable urban land use compared to the world theory and practice has almost not been elaborated by the professionals in Serbia. This paper's starting point is that it is important to analyze and apply this topic, not only for the master plan level but also for the more detailed levels of planning and for smaller spatial entities/complexes in the cities, focusing on the morphological implications of sustainable urban land use as the topic relevant from the architect/urban planner point of view. After the definition of the notion of sustainable urban land use and the theoretical basis has been defined in the introductory explications, followed by a brief review of that topic's presence in Serbia, the point of view has been explained - namely, focusing on one single aspect (morphology) followed by a review of relevant criteria of other aspects of sustainable urban land use (economical, ecological and social aspects). The conclusion derived by synthesis represents the recommendation for a possible practice/methodology for planner's approach to the sustainable urban land use from the viewpoint of the morphology aspect.

BIM Application in Documenting and Recreating Lost Architectural Heritage

2019 ◽  
pp. 112-141
Author(s):  
Paola Casu ◽  
Claudia Pisu
Keyword(s):  
Nineteenth Century ◽  
Cultural Heritage ◽  
3D Models ◽  
Full Potential ◽  
Architectural Heritage ◽  
Research Focus ◽  
Digital Archiving ◽  
Food Market ◽  
Definition Of

The digital archiving process of complex historical architectural 3D models is a key point in the field of tangible cultural heritage. A lot of research focus on the definition of methodologies and tools that exploit the full potential of ICT applied to the documentation of cultural heritage. This chapter illustrates a part of a study in this line of investigation. It focuses on the use of BIM for the reconstruction of lost architectural heritage. BIM will be applied to virtual reconstruct the nineteenth-century covered food market of Cagliari that was demolished in 1957. Thanks to the properties of BIM to enter information related to each element constituting a building, every part of the model will be accompanied by information on the degree of reliability and references adopted for its creation. In this way, each family of elements could more easily and knowingly be reused for other similar projects.

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