scholarly journals Accurate Algorithms for Spatial Operations on the Spheroid in a Spatial Database Management System

2021 ◽  
Vol 11 (11) ◽  
pp. 5129
Author(s):  
José Carlos Martínez-Llario ◽  
Sergio Baselga ◽  
Eloína Coll
Keyword(s):  
Spatial Analysis ◽  
Minimum Distance ◽  
Traditional Approach ◽  
Google Earth ◽  
Database Management System ◽  
Analysis Software ◽  
Software Products ◽  
Spatial Operators ◽  
High Degree ◽  
Spatial Database Management System

Some of the most powerful spatial analysis software solutions (Oracle, Google Earth Engine, PostgreSQL + PostGIS, etc.) are currently performing geometric calculations directly on the ellipsoid (a quadratic surface that models the earth shape), with a double purpose: to attain a high degree of accuracy and to allow the full management of large areas of territory (countries or even continents). It is well known that both objectives are impossible to achieve by means of the traditional approach using local mathematical projections and Cartesian coordinates. This paper demonstrates in a quantitative methodological way that most of the spatial analysis software products make important deviations in calculations regarding to geodesics, being the users unaware of the magnitude of these inaccuracies, which can easily reach meters depending on the distance. This is due to the use of ellipsoid calculations in an approximate way (e.g., using a sphere instead of an ellipsoid). This paper presents the implementation of two algorithms that solve with high accuracy (less than 100 nm) and efficiently (few iterations) two basic geometric calculations on the ellipsoid that are essential to build more complex spatial operators: the intersection of two geodesics and the minimum distance from a point to a geodesic.

scholarly journals Multimodal analgesia in bariatric surgery

2016 ◽  
Vol 10 (4) ◽  
pp. 254-261
Author(s):  
M. I Neimark ◽  
Roman V. Kiselev
Keyword(s):  
Bariatric Surgery ◽  
Regional Anesthesia ◽  
Traditional Approach ◽  
Multimodal Analgesia ◽  
Pharmacological Agents ◽  
Perioperative Analgesia ◽  
High Degree ◽  
Mandatory Use ◽  
Different Levels

This review is devoted to the treatment of postoperative pain in bariatric surgery. At present, the prevalence of patients with a high degree of obesity is an epidemic that leads steadily growing number of bariatric operations. Showing the risk factors in the traditional approach to the use of opioids in these patients, as well as the consequences of inadequate analgesia in these patients. Details are presented modern pharmacological agents acting on different levels nociceptive system. Substantiates the role of a multi-modal approach to perioperative analgesia, mandatory use of regional anesthesia. The attention to the visualization neuroaxial structures using ultrasound in the context of the implementation of the efficacy and safety of regional anesthesia in patients with morbid obesity. Possible prospects for pain control in bariatric surgery.

Spatial analytics of self-organized vegetation pattern in semi-arid regions: an example on tiger-bush patterns in Sudan

2021 ◽  
Author(s):  
Christoph Hinz ◽  
Konlavach Nengsuwan ◽  
Daniel Cavieds-Voullieme
Keyword(s):  
Spatial Analysis ◽  
Arid Regions ◽  
Numerical Models ◽  
Google Earth ◽  
Vegetation Patterns ◽  
Strong Positive Correlation ◽  
Positive Correlation ◽  
Geometrical Properties ◽  
Principal Axes ◽  
Semi Arid

<p>The concept of local-scale interactions of spatially periodic vegetation patterns are well known in arid and semi-arid regions. The vegetation patterns are easily observable from aerial and satellite photography. Additionally, various mathematical models have been developed to reproduce the patterns observed in nature, aimed towards understanding the driving factors leading to pattern properties. Several studies exist attempting to analyse spatial properties of these patterns, their spatial distribution and their relationship to  topography and climate. However, there are limitations in how these studies provide spatially-distributed statistics, and on the specifics of vegetation patch and band geometries, making it difficult to compare to model predictions. </p><p>This study proposes  a new workflow (implemented in R) to measure geometric  characteristics of vegetation bands and patches. We use high-resolution satellite imagery as the base dataset. Color filters are used to binarise and identify individual patches/bands of arbitrary irregular shapes. We then compute different geometrical properties, such as  patch-size, separation between them, orientation, among others. Additionally, the principal axes of each patch/band are identified, and used to measure characteristic lengths and widths, for which statistics are then computed, and can be represented in spatial subdomains to allow for spatial analysis at different scales. The strategy can also be easily applied to modelling results, thus facilitating comparison, and the algorithm is flexible enough to yield different forms of patterns and spatial extent.</p><p>As a test case, we apply this workflow to a study site (11.05 N, 28.35 E) in Kordofan, south Sudan (a region previously reported and documented in the literature), using Google Earth Imagery as input. For this domain (3500 x 1400 m), the  results show that the length of the patches has a strong positive correlation with their width. Additionally, the length and the average nearest neighbor distance displayed a small positive correlation to the elevation. Using the available ALOS topography, the results also confirm that that 92% of the bands in our study area are oriented perpendicularly to the slope direction, as is expected from these systems. </p><p>This test is a first step into applying this workflow to a larger extend within Kordofan and other regions known to exhibit vegetation bands (tiger bush in wester Africa, Australia, Nevada) and perform extensive geometric and spatial analysis of the bands, as well as simulated banded systems obtained from numerical models.</p><p>Keywords: Vegetation patterns, Self-organization, Tiger-bush, Geometric analysis, Oriented direction</p>

Nature of Geographic Knowledge Bases

2019 ◽  
pp. 94-125
Author(s):  
Robert Laurini
Keyword(s):  
Spatial Analysis ◽  
Urban Planning ◽  
Data Acquisition ◽  
Knowledge Bases ◽  
Geographic Information ◽  
Software Products ◽  
Geographic Feature ◽  
Geographic Knowledge ◽  
Planning Experts ◽  
Gis Software

In many domains such as environmental and urban planning, experts need to make reasoning and propose solutions. However marketed GIS software products are limited to store, display geographic information together with additional tools such as in spatial analysis, but they do not offer users the real functionalities which are useful for territorial intelligence. This first step is to propose novel models to represent this kind of knowledge needing not only to integrate geographic aspects, but also be independent of data acquisition technologies (satellite images, laser, crowdsourcing, etc.) and able to be used in different languages. After the definitions of geographic ontologies (to organize geographic feature vocabulary) and gazetteers (to structure toponyms in various languages), various examples will be presented in order to extract geographic semantics. A special attention will be devoted to geographic rules.

Nature of Geographic Knowledge Bases

2017 ◽  
pp. 29-60 ◽  
Author(s):  
Robert Laurini
Keyword(s):  
Spatial Analysis ◽  
Urban Planning ◽  
Data Acquisition ◽  
Knowledge Bases ◽  
Geographic Information ◽  
Software Products ◽  
Geographic Feature ◽  
Geographic Knowledge ◽  
Planning Experts ◽  
Gis Software

In many domains such as environmental and urban planning, experts need to make reasoning and propose solutions. However marketed GIS software products are limited to store, display geographic information together with additional tools such as in spatial analysis, but they do not offer users the real functionalities which are useful for territorial intelligence. This first step is to propose novel models to represent this kind of knowledge needing not only to integrate geographic aspects, but also be independent of data acquisition technologies (satellite images, laser, crowdsourcing, etc.) and able to be used in different languages. After the definitions of geographic ontologies (to organize geographic feature vocabulary) and gazetteers (to structure toponyms in various languages), various examples will be presented in order to extract geographic semantics. A special attention will be devoted to geographic rules.

Applying Mantel’s spatial method to the case of restaurants

2020 ◽  
Vol 35 (4) ◽  
pp. 45-71
Author(s):  
Amélie Clauzel
Keyword(s):  
Spatial Analysis ◽  
Consumer Behaviour ◽  
Spatial Distance ◽  
Open Spaces ◽  
Shared Spaces ◽  
Spatial Method ◽  
High Degree ◽  
First Time

Most conventional spatial analysis approaches that are used to study the effects of interpersonal spacing are positioned on urban geographical scales and are, therefore, applicable to open spaces. This article presents the challenges and limitations of the Mantel method, which is particularly appropriate for co-presence situations in enclosed spaces, and also shows how it is implemented. Traditionally used in biostatistics and ecology, the method is deployed here for the first time in the field of consumer behaviour. When applied to the case of restaurants, it helps to identify the effects of (here, socio-spatial) distance on the greater or lesser similarity of choices between customer groups and their spending. Because it allows a high degree of use across disciplines, particularly in management sciences, the Mantel method may interest practitioners seeking to (re-)arrange shared spaces, such as workspaces, shows, aeroplane areas, spas or condominium meetings.

CQPweb — combining power, flexibility and usability in a corpus analysis tool

2012 ◽  
Vol 17 (3) ◽  
pp. 380-409 ◽  
Author(s):  
Andrew Hardie
Keyword(s):  
Data Model ◽  
Ease Of Use ◽  
Corpus Analysis ◽  
Analysis Tool ◽  
Analysis Software ◽  
Web Based ◽  
Query System ◽  
Analysis System ◽  
High Degree ◽  
Very High

CQPweb is a new web-based corpus analysis system, intended to address the conflicting requirements for usability and power in corpus analysis software. To do this, its user interface emulates the BNCweb system. Like BNCweb, CQPweb is built on two separate query technologies: the IMS Open Corpus Workbench and the MySQL relational database. CQPweb’s main innovative feature is its flexibility; its more generalised data model makes it compatible with any corpus. The analysis options available in CQPweb include: concordancing; collocations; distribution tables and charts; frequency lists; and keywords or key tags. An evaluation of CQPweb against criteria earlier laid down for a future web-based corpus analysis tool suggests that it fulfils many, but not all, of the requirements foreseen for such a piece of software. Despite some limitations, in making a sophisticated query system accessible to untrained users, CQPweb combines ease of use, power and flexibility to a very high degree.

scholarly journals SPATIAL DMBS ARCHITECTURE FOR A FREE AND OPEN SOURCE BIM

2017 ◽  
Vol XLII-2/W5 ◽  
pp. 467-473 ◽  
Author(s):  
S. Logothetis ◽  
E. Valari ◽  
E. Karachaliou ◽  
E. Stylianidis
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
Computer Aided Design ◽  
Database Management System ◽  
Technological Advancement ◽  
Single Application ◽  
Building Information Modelling ◽  
Building Information ◽  
Aided Design ◽  
Spatial Database Management System

Recent research on the field of Building Information Modelling (BIM) technology, revealed that except of a few, accessible and free BIM viewers there is a lack of Free & Open Source Software (FOSS) BIM software for the complete BIM process. With this in mind and considering BIM as the technological advancement of Computer-Aided Design (CAD) systems, the current work proposes the use of a FOSS CAD software in order to extend its capabilities and transform it gradually into a FOSS BIM platform. Towards this undertaking, a first approach on developing a spatial Database Management System (DBMS) able to store, organize and manage the overall amount of information within a single application, is presented.

scholarly journals The interception of vagueness in occurrence of plants modeling with using map algebra

2009 ◽  
Vol 57 (6) ◽  
pp. 143-152
Author(s):  
Jitka Machalová
Keyword(s):  
Spatial Analysis ◽  
Fuzzy Sets ◽  
Information And Communication Technologies ◽  
Relevant Information ◽  
Map Algebra ◽  
Correct Definition ◽  
Information And Communication ◽  
Definition Of ◽  
Ship Function ◽  
High Degree

Information plays an important role in process of decision-making. Information and communication technologies give to the decision-makers not only relevant information, but they help in their interpretation. The basic advantage of fuzzy logic is the capability mathematic catch up the information, which is phrased. If we have set of elements, in that every element is characterised by grade of pertinence (member ship function), we call it fuzzy set. Map algebra is instrument that allows working up the raster representation of reality with using language of the map algebra. The using fuzzy sets for solving spatial problems is qualified by process in 3 steps: a) the correct definition of the type of member ship function, 2) the reserve of quality of input data, and 3) to modelling defined fuzzy sets by expert and the implementation of spatial analysis above them. The article has the goal, exemplify of modelling of occurrence of Epipogium aphyllum in the Czech Republic, to propose the way of spatial analysis above fuzzygeoelements with using map algebra. Only 4 restrictive conditions input to model, and the size of pixel in layer is 10 m. Fuzzy sets are realised above selected raster ­layers, that were defined in the step 1) by instruments of the map algebra. The resulting model specifies the places with documented occurrence with the high degree of member ship function.

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