Institution
Naval School
Education•Almada, Portugal•
About: Naval School is a education organization based out in Almada, Portugal. It is known for research contribution in the topics: Computer science & Self-organizing map. The organization has 30 authors who have published 52 publications receiving 396 citations. The organization is also known as: Royal Academy of the Midshipmen & Portuguese and Brazilian midshipmen academies separation.
Topics: Computer science, Self-organizing map, Cluster analysis, Artificial neural network, Geospatial analysis
Papers published on a yearly basis
Papers
TL;DR: In this study a variant of the SOM-algorithm is proposed, the GEO3DSOM, capable of explicitly incorporating three-dimensional spatial knowledge into the algorithm, and it is compared to the standard SOM in analyzing an artificial data set and a hydrochemical data set.
Abstract: . The use of unsupervised artificial neural network techniques like the self-organizing map (SOM) algorithm has proven to be a useful tool in exploratory data analysis and clustering of multivariate data sets. In this study a variant of the SOM-algorithm is proposed, the GEO3DSOM, capable of explicitly incorporating three-dimensional spatial knowledge into the algorithm. The performance of the GEO3DSOM is compared to the performance of the standard SOM in analyzing an artificial data set and a hydrochemical data set. The hydrochemical data set consists of 131 groundwater samples collected in two detritic, phreatic, Cenozoic aquifers in Central Belgium. Both techniques succeed very well in providing more insight in the groundwater quality data set, visualizing the relationships between variables, highlighting the main differences between groups of samples and pointing out anomalous wells and well screens. The GEO3DSOM however has the advantage to provide an increased resolution while still maintaining a good generalization of the data set.
65 citations
TL;DR: This paper presents the GeoSOM suite as a tool designed to bridge the gap between clustering and the typical geographic information science objectives and needs, and presents a case study, based on census data from Lisbon, exploring the Geo SOM suite features and exemplifying its use in the context of exploratory data analysis.
52 citations
TL;DR: This paper presents a new method for building cartograms, based on self-organizing neural networks (Kohonen's self‐organizing maps or SOM), which is competitive and can perform better then existing algorithms.
Abstract: The basic idea of a cartogram is to distort a geographical map by substituting the geographic area of a region by some other variable of interest. The objective is to rescale each region according to the value of the variable of interest while keeping the map, as much as possible, recognizable. There are several algorithms for building cartograms. None of these methods has proved to be universally better than any other, since the trade-offs made to get the correct distortion vary. In this paper we present a new method for building cartograms, based on self-organizing neural networks (Kohonen's self-organizing maps or SOM). The proposed method is widely available and is easy to carry out, and yet has several appealing properties, such as easy parallelization, making up a good tool for geographic data presentation and analysis. We present a series of tests on different problems, comparing the new algorithm with existing ones. We conclude that it is competitive and, in some circumstances, can perform better then existing algorithms.
45 citations
TL;DR: A method is presented for spatial clustering that integrates the visualization of both perspectives of a SOM: linking its output space, defined in up to three dimensions (3D), to the cartographic representation through a ordered set of colors; and exploring the use of border lines among geo-referenced elements, computed according to the distances in the input data space between their Best Matching Units.
40 citations
TL;DR: In this article, the sensitivity of the buckling and post-buckling behavior of imperfect steel plates used in ship and related marine structures when subject to variations in their initial conditions was investigated.
39 citations
Authors
Showing all 32 results
| Name | H-index | Papers | Citations |
|---|---|---|---|
| Victor Lobo | 14 | 84 | 1161 |
| R. P. C. Sampaio | 11 | 18 | 942 |
| Nuno Pessanha Santos | 7 | 14 | 94 |
| Miguel Moreira | 6 | 24 | 99 |
| M. Filomena Teodoro | 6 | 56 | 172 |
| Anacleto Correia | 6 | 57 | 133 |
| Jorge Gorricha | 4 | 6 | 61 |
| Armindo Dias da Silva Frias | 3 | 10 | 21 |
| Valter Vairinhos | 3 | 12 | 17 |
| Suzana Lampreia | 3 | 18 | 25 |
| Fernando Correia | 3 | 4 | 79 |
| José B. Rebelo | 2 | 4 | 8 |
| Sofia S. Teles | 2 | 3 | 4 |
| Teresa Leonor Ribeiro Cardoso Martins Morgado | 2 | 12 | 15 |
| Victor Fernando Placido da Conceicao | 2 | 5 | 18 |
Related Institutes (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 5 |
| 2023 | 2 |
| 2022 | 5 |
| 2021 | 8 |
| 2020 | 4 |
| 2019 | 2 |