Union and intersection of Level-2 fuzzy regions

In many applications spatial data are considered, yet this data quite often are prone to uncertainty and imprecision. For this purpose, fuzzy regions have been developed. Our initial model, a fuzzy set over a two dimensional domain, allowed for both fuzzy regions and fuzzy points to be modelled. The model still had some shortcomings: all points where treated independently, and it was not possible to group points together. In some situations this makes the model more imprecise and uncertain than it should have been. Furthermore, while the model allowed for the representations of both fuzzy regions and fuzzy locations, simply by changing the interpretation of the fuzzy set, this interpretation needed to be specified as meta information. The model was extended to a level-2 fuzzy region to overcome these limitations, but this has an impact on operations. In this contribution, intersection and union will be discussed

Contourline based modelling of vague regions

This paper introduced a model based on contour lines to represent a vague region modeled as a fuzzy set. The model allows the user to adjust the accuracy of the membership function to the needs of the application and can enforce the continuity of this function whenever desirable

Fuzziness in spatial databases and GIS

This paper explains why and how spatial databases and geographic information systems can benefit from an appropriate representation of imprecise and/or uncertain information. Not only are the imprecission and uncertainty inherent to the data to be modeled, they also appear in both various queries and the result of various queries

Adapting TIN layers to represent fuzzy geographic information

One of the latest research topics in geographic information systems (GIS for short) is the modeling of fuzzy (imprecise or vague) and/or uncertain information. A GIS usually contains large amounts of data and requires very specific operations to manage (geographic) data, both of which are described in a geographic database model. In this paper, the basic concepts for a data model describing the structure of and operations on fuzzy or uncertain geographic information are presented. Specific for the presented model is the adaptation of triangulated irregular networks (TINs), commonly used in GIS (e.g. to model altitudes), for the modelling of fuzzy (geographic) data

Fuzzy and uncertain spatio-temporal database models : a constraint-based approach

In this paper a constraint-based generalised object-oriented database model is adapted to manage spatiotemporal information. This adaptation is based on the definition of a new data type, which is suited to handle both temporal and spatial information. Generalised constraints are used to describe spatio-temporal data, to enforce integrity rules on databases, to specify the formal semantics of a database scheme and to impose selection criteria for information retrieval

Higher Reasoning with Level-2 Fuzzy Regions

Spatial data is quite often is prone to uncertainty and imprecision. For this purpose, fuzzy regions have been developed: they basically consist of a fuzzy set over a two dimensional domain, allowing for both fuzzy regions and fuzzy points to be modelled. The model is extended to a level-2 fuzzy region to overcome some limitations, but this has an impact on operations. In this contribution, we will look into the construction of and combination of existing data to yield level-2 fuzzy regions

Two Groups of Cocirculating, Epidemic Clostridiodes difficile Strains Microdiversify through Different Mechanisms

Clostridiodes difficile strains from the NAPCR1/ST54 and NAP1/ST01 types have caused outbreaks despite of their notable differences in genome diversity. By comparing whole genome sequences of 32 NAPCR1/ST54 isolates and 17 NAP1/ST01 recovered from patients infected with C. difficile we assessed whether mutation, homologous recombination (r) or nonhomologous recombination (NHR) through lateral gene transfer (LGT) have differentially shaped the microdiversification of these strains. The average number of single nucleotide polymorphisms (SNPs) in coding sequences (NAPCR1/ST54 = 24; NAP1/ST01 = 19) and SNP densities (NAPCR1/ST54 = 0.54/kb; NAP1/ST01 = 0.46/kb) in the NAPCR1/ST54 and NAP1/ST01 isolates was comparable. However, the NAP1/ST01 isolates showed 3× higher average dN/dS rates (8.35) that the NAPCR1/ST54 isolates (2.62). Regarding r, whereas 31 of the NAPCR1/ST54 isolates showed 1 recombination block (3,301–8,226 bp), the NAP1/ST01 isolates showed no bases in recombination. As to NHR, the pangenome of the NAPCR1/ST54 isolates was larger (4,802 gene clusters, 26% noncore genes) and more heterogeneous (644 ± 33 gene content changes) than that of the NAP1/ST01 isolates (3,829 gene clusters, ca. 6% noncore genes, 129 ± 37 gene content changes). Nearly 55% of the gene content changes seen among the NAPCR1/ST54 isolates (355 ± 31) were traced back to MGEs with putative genes for antimicrobial resistance and virulence factors that were only detected in single isolates or isolate clusters. Congruently, the LGT/SNP rate calculated for the NAPCR1/ST54 isolates (26.8 ± 2.8) was 4× higher than the one obtained for the NAP1/ST1 isolates (6.8 ± 2.0). We conclude that NHR-LGT has had a greater role in the microdiversification of the NAPCR1/ST54 strains, opposite to the NAP1/ST01 strains, where mutation is known to play a more prominent role.Ministerio de Ciencia, Tecnología y Telecomunicaciones/[803-B4-510]/MICITT/Costa RicaFederal State of Lower Saxony/[VWZN2889/3215]//Baja SajoniaGerman Center for Infection Research/[ 8000-105-3]/DZIF/AlemaniaUniversidad de Costa Rica/[803-B5-770]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET)UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiologí