João Moura Pires

João Moura Pires
Universidade NOVA de Lisboa | NOVA · Department of Informatics (DI)

PhD

About

74
Publications
16,740
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412
Citations
Citations since 2016
26 Research Items
219 Citations
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2016201720182019202020212022010203040
2016201720182019202020212022010203040

Publications

Publications (74)
Chapter
Air quality is an important issue that impacts who live in cities. During COVID-19 pandemic, it becomes clear that low air quality can increase the effects of the disease. It is very important that in this era of Big Data and Smart Cities we use technology to address health issues like air quality problems. Often, air quality is monitored using dat...
Chapter
O período entre 2018 e 2022 mostrou-nos que o problema dos incêndios à escala global não está a diminuir, antes pelo contrário. Parece que as consequências das alterações climáticas já estão a afectar a ocorrência de incêndios florestais em várias partes do Mundo, de uma forma que só esperaríamos que acontecesse vários anos mais tarde. Em muitos pa...
Article
Full-text available
Datasets collecting demographic and socio-economic statistics are widely available. Still, the data are often only released for highly aggregated geospatial areas, which can mask important local hotspots. When conducting spatial analysis, one often needs to disaggregate the source data, transforming the statistics reported for a set of source zones...
Article
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Every year, wildfires strike the Portuguese territory and are a concern for public entities and the population. To prevent a wildfire progression and minimize its impact, Fuel Management Zones (FMZs) have been stipulated, by law, around buildings, settlements, along national roads, and other infrastructures. FMZs require monitoring of the vegetatio...
Preprint
Full-text available
Mapping structures such as settlements, roads, individual houses and any other types of artificial structures is of great importance for the analysis of urban growth, masking, image alignment and, especially in the studied use case, the definition of Fuel Management Networks (FGC), which protect buildings from forest fires. Current cartography has...
Article
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Crimes, forest fires, accidents, infectious diseases, or human interactions with mobile devices (e.g., tweets) are being logged as spatiotemporal events. For each event, its geographic location, time and related attributes are known with high levels of detail (LoDs). The LoD plays a crucial role when analyzing data, as it can highlight useful patte...
Conference Paper
Full-text available
O mapeamento de estruturas tais como aglomerados populacionais, estradas, casas individuais e qualquer outro tipo de estrutura artificial é de grande importância para a análise do crescimento urbano, criação de máscaras, alinhamento de imagens e, especialmente no caso de uso estudado, definição das faixas de gestão de combustível (FGC). As cartas e...
Chapter
Soil classification is a method of encoding the most relevant information about a given soil, namely its composition and characteristics, in a single class, to be used in areas like agriculture and forestry. In this paper, we evaluate how confidently we can predict soil classes, following the World Reference Base classification system, based on the...
Article
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High-resolution population grids built from historical census data can ease the analyses ofgeographical population changes, at the same time also facilitating the combination of populationdata with other GIS layers to perform analyses on a wide range of topics. This article reports onexperiments with a hybrid spatial disaggregation technique that c...
Preprint
Full-text available
A determinação dos limites reais de parcelas agrícolas a partir de imagens de deteção remota é fundamental para construir cadastros agrícolas atempadamente, diminuindo os custos da sua obtenção. Para esse efeito, foram recolhidos vários produtos Sentinel-2, correspondentes ao ano de 2018, coincidentes com uma área agrícola em Vale de Cavalos com ce...
Article
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While statistical information on socio-economic activities is widely available, the data are often collected or released only at a relatively aggregated level. In these aggregated forms, the data are useful for broad-scale assessments, although we often need to disaggregate the source data in order to provide more localized estimates, and in order...
Conference Paper
Full-text available
In this paper, an approach to estimate the severity of stator winding short-circuit faults in squirrel-cage induction motors based on the Cubist model is proposed. This is accomplished by scoring the unbalance in the current and voltage waveforms as well as in Park’s Vector, both for current and voltage. The proposed method presents a systematic co...
Conference Paper
This paper analyses and shows the need of a client side web API devoted to present and explore spatial information through thematic maps. We define a set of requirements for such API, most notably the ability to process datasets with many millions of points, allowing full interactivity, providing a high level of abstraction and defining clear paths...
Conference Paper
Several approaches have been proposed to model spatiotemporal phenomena at multiple LoDs, in particularly, under the granular computing research area, where a granularities-based model was proposed. Such model stands out from the related literature, but has two major limitations. On one hand, it has difficulties for describing regions, intervals of...
Article
Full-text available
A personal collection of photos shows large variability in the depicted items, making difficult a fully automated solution to cope with sensory and semantic gaps. Emotions and non-visual contextual information can be very important to address those problems. Manual annotations are key, but their time-consuming nature alienate users from doing them....
Conference Paper
The field of Information Visualization seeks to identify the general principles of visualization, and makes use of these principles to propose new forms of visualization for specific types of data. Included in these different data types, it was identified a data type which was not thoroughly explored. The notion of entities where each entity is com...
Conference Paper
Full-text available
There are many spatiotemporal events with high levels of detail (LoDs) being collected in many phenomena. The LoD of analysis plays a crucial role in the user’s perception of phenomena. From one LoD to another, some patterns can be easily perceived or different patterns may be detected. Standard practices work on a single LoD driven by the user in...
Article
Full-text available
Due to the constant technological advances and massive use of electronic devices, the amount of data generated has increased at a very high rate, leading to the urgent need to process larger amounts of data in less time. In order to be able to handle these large amounts of data, several techniques and algorithms have been developed in the area of k...
Chapter
There are many spatiotemporal events with high levels of detail (LoDs) being collected in many phenomena. The LoD of analysis plays a crucial role in the user’s perception of phenomena. From one LoD to another, some patterns can be easily perceived or different patterns may be detected. Standard practices work on a single LoD driven by the user in...
Article
Full-text available
Nowadays, road accidents are a major public health problem, which increase is forecasted if road safety is not treated properly, dying about 1.2 million people every year around the globe. In 2012, Portugal recorded 573 fatalities in road accidents, on site, revealing the largest decreasing of the European Union for 2011, along with Denmark. Beyond...
Article
Huge amounts of data are available for analysis in nowadays organizations, which are facing several challenges when trying to analyze the generated data with the aim of extracting useful information. This analytical capability needs to be enhanced with tools capable of dealing with big data sets without making the analytical process an arduous task...
Conference Paper
Spatio-temporal clustering is a subfield of data mining that is increasingly gaining more scientific attention due to the advances of location-based devices that register position, time and, in some cases, other attributes. Spatio-temporal clustering intends to group objects based in their spatial and temporal similarity helping to discover interes...
Conference Paper
Full-text available
Spatio-temporal data are collected at high levels of detail (LoDs). Both spatial and temporal characteristics of data can be expressed at different LoDs. Depending on the phenomenon and the analytical goal, different LoDs can be suitable for a user’s analysis since different LoDs may provide different perceptions of a phenomenon. It is crucial to m...
Article
Full-text available
Reasoning about spatio-temporal phenomena requires the adoption of common granularities that facilitate and enhance the comprehension of a particular phenomenon. In our day-to-day activities, spatial granules like state, province or country, and temporal granules like day, month or year, are used to index facts and to allow reasoning adopting the l...
Conference Paper
Nowadays, the massive amount of spatio-temporal data available exceeds the human capability to absorb them (i.e., to achieve insights). A possible approach to address this issue is through less detailed representations of phenomena so that the data complexity can be decreased making easier for the users to achieve meaningful insights. In this paper...
Conference Paper
Large amounts of spatio-temporal data are continuously collected through the use of location devices or sensor technologies. One of the techniques usually used to obtain a first insight on data is clustering. The Shared Nearest Neighbour (SNN) is a clustering algorithm that finds clusters with different densities, shapes and sizes, and also identif...
Conference Paper
Full-text available
People produce an increasing amount of digital photos to document events. Searching for a specific event can result in more photos than people can handle, making difficult judging their relevance. This paper presents a new algorithm, that summarises a set of photos described by attributes at different concept levels. It addresses the well-known hum...
Conference Paper
Several clustering algorithms have been extensively used to analyze vast amounts of spatial data. One of these algorithms is the SNN (Shared Nearest Neighbor), a density-based algorithm, which has several advantages when analyzing this type of data due to its ability of identifying clusters of different shapes, sizes and densities, as well as the c...
Conference Paper
Nowadays, organizations are facing several challenges when they try to analyze generated data with the aim of extracting useful information. This analytical capacity needs to be enhanced with tools capable of dealing with big data sets without making the analytical process a difficult task. Clustering is usually used, as this technique does not req...
Conference Paper
Full-text available
Spatio-temporal clustering is a sub field of data mining that is increasingly gaining more scientific attention due to the advances of location-based or environmental devices that register position, time and, in some cases, other semantic attributes. This process pretends to group objects based in their spatial and temporal similarity helping to di...
Chapter
Many organisations need to extract useful information from huge amounts of movement data. One example is found in maritime transportation, where the automated identification of a diverse range of traffic routes is a key management issue for improving the maintenance of ports and ocean routes, and accelerating ship traffic. This paper addresses,in a...
Article
The emergence of the SOLAP concept supports map visualization for improving data analysis, enhancing the decision making process. However, in this environment, maps can easily become cluttered losing the benefits that triggered the appearance of this concept. In order to overcome this problem, a post-processing model is proposed, which relies on Ge...
Conference Paper
Sharing and integrating information across multiple autonomous and heterogeneous data sources has emerged as a strategic requirement in modern business. We deal with this problem by proposing a declarative approach based on the creation of a reference model and perspective schemata. The former serves as a common semantic meta-model, while the latte...
Conference Paper
Full-text available
The increasing availability of mobility data and the awareness of its importance and value have been motivating many researchers to the development of models and tools for analyzing movement data. This paper presents a brief survey of significant research works about modeling, processing and visualization of data about moving objects. We identified...
Conference Paper
The main purpose of SOLAP concept was to take advantage of the map visualization improving the analysis of data and enhancing the associated decision making process. However, in this environment, the map can easily become cluttered losing the benefits that triggered the appearance of this concept. In order to overcome this problem we propose a post...
Conference Paper
Full-text available
Sharing and integrating information among multiple heterogeneous and autonomous databases has emerged as a strategic requirement in modern enterprises. We deal with this problem by proposing a declarative approach based on the creation of a reference model and perspective schemata. The former provides a common semantic, while the latter connects sc...
Conference Paper
Full-text available
In every Online Analytical Processing (OLAP) cube, there are certain type of measures, generally referred as facts, that must be treated carefully, due to their non-addictive nature. This means they can't be added directly to present a summarised result. In this paper, the authors focused on a specific type of non-addictive facts, quota sampled bas...
Conference Paper
Today's Information Systems and Enterprise Applications require extensive use of Metadata information. In Information Systems, metadata helps in integration and modelling their various components and computational processes, while in Enterprises metadata can describe business and management models, human or physical resources, among others. This pa...
Conference Paper
Full-text available
The ETL problematic is becoming progressively less specific to the traditional data-warehousing domain and is being extended to the processing of textual data. The World Wide Web appears as a major source of textual information, following a human-readable semi-structured format, referring to multiple domains, some of them highly complex. Traditiona...
Conference Paper
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Audiometer systems provide enormous amounts of detailed TV watching data. Several relevant and interdependent factors may influence TV viewers' behavior. In this work we focus on the tune factor and derive temporal patterns of TV watching, based on panel data. Clustering base attributes are originated from 1440 binary minute-related attributes, cap...
Conference Paper
Full-text available
This paper presents a category of on-line analytical processing (OLAP) tool intended to explore data related to space i.e. spatial data. The tool, designated SOLAP, integrates concepts from two different worlds, namely, geographic information systems (GIS) and OLAP. OLAP systems are developed for interactive and rapid analysis of large amounts of d...
Article
Full-text available
System interface specification documents are hard to maintain up-dated, mainly due to the fact that the frequency of new improvements/ addi-tions of new systems is high. To facilitate maintenance of existing interface specifications and enhance its usability, the development of a formal language specification, to address the definition and descript...
Conference Paper
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Space applications' users have been relying for the past decades on custom developed software tools capable of addressing short term necessities during critical Spacecraft control periods. Advances in computing power and storage solutions have made possible the development of innovative decision support systems. These systems are capable of providi...
Article
Full-text available
Today's Information Systems include many components and computational processes such as Data Warehouses, Data Marts, ETL processes, Data Analysis tools, etc. An appropriate integration of theses components requires the extensive use of metadata. However the representation, consolidation, management, and access to this metadata information can cause...
Conference Paper
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Keeping the spacecraft (S/C) healthy and productive is the responsibility and the main concern of the S/C flight control team (FCT). Space weather includes effects and conditions that favour the aging of a S/C and its instruments, e.g. degradation of sensors and solar arrays by charged particles and single event upsets (SEU). It is worth to stress...
Conference Paper
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Space weather has been directly and indirectly identified as the source for a large percentage of spacecraft abnormal behaviours (through high radiation levels emissions, solar flares and magnetically induced fields). Nowadays spacecraft control teams lack the assistance of a system that can provide real-time information on space weather conditions...
Article
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The radiation environment encountered in space by satellites is extremely variable and depends mainly on the satellite position and space weather. Although models for the concerned processes are available, most of them only represent the average conditions and neglect the dynamics of the system. Accurate prediction of the radiation environment rema...
Conference Paper
Full-text available
Space weather refers to conditions on the sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and that affect human life or health(1). Such influence is particularly strong on spacecrafts by reducing the mission lifetime and c...
Article
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In this paper we investigate why solving leximin fuzzy constraint satisfaction problems (FCSP) with non-enumerative algorithms, such as hill-climbing, simulated annealing and genetic algorithms, provide disappointing results. Specifically, we analyse the structure and properties of the leximin FCSPs and its influence on the search strategy of non-e...
Conference Paper
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A tuple of fuzzy constraints defined on a discrete satisfaction scale defines a lattice structure, called relaxation space, made of the tuples of level cuts of the fuzzy constraints, equipped with the partial order induced by the scale ordering. Then choosing a way of combining the fuzzy constraints has two joint effects: usually a completion of th...
Conference Paper
Fuzzy sets naturally model elastic constraints, the fuzzy constraints satisfaction problem (FCSP) enables the introduction of different kinds of flexibility. Levels of priority can be attached to constraints, and satisfaction levels can be fuzzily thresholded. Fuzzy constraints are aggregated by min operation into a fuzzy set membership function to...
Article
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In this paper we investigate the determination of starting points for non-enumera- tive optimization algorithms in order to solve discrimin and leximin Fuzzy Constraint Satisfac- tion Problems (FCSP). Discrimin and leximin are two refinements of the min - based ordering (in FCSP, fuzzy constraint are aggregated by min operation). Specifically, the...