A5008236312- Indoor and Outdoor Localization Technologies
- Human Mobility and Location-Based Analysis
- Context-Aware Activity Recognition Systems
- Speech and Audio Processing
- Data Management and Algorithms
- Underwater Vehicles and Communication Systems
- Millimeter-Wave Propagation and Modeling
- Geographic Information Systems Studies
- Wireless Networks and Protocols
- Mobile Crowdsensing and Crowdsourcing
- Optical Wireless Communication Technologies
- Radio Wave Propagation Studies
- Brazilian Legal Issues
- Opportunistic and Delay-Tolerant Networks
- Bluetooth and Wireless Communication Technologies
- Energy Efficient Wireless Sensor Networks
- Semiconductor Lasers and Optical Devices
- Wireless Communication Networks Research
- Social and Political Issues
- GNSS positioning and interference
- Air Quality Monitoring and Forecasting
- Constraint Satisfaction and Optimization
- Cardiac, Anesthesia and Surgical Outcomes
- Literature, Culture, and Criticism
- IoT and Edge/Fog Computing
University of Minho
2015-2024
Hospital de São João
2013-2023
Centro de Computação Gráfica
2022
Universitat Jaume I
2021
University of Trento
2020
Universidade Estadual Paulista (Unesp)
2011-2017
Instituto Superior de Ciencias Sociais e Relações Internacionais
2017
Centrus Diagnósticos por Imagem
2017
San Antonio College
2012-2013
University of Coimbra
2012-2013
Location information for events, assets, and individuals, mostly focusing on two dimensions so far, has triggered a multitude of applications across different verticals, such as consumer, networking, industrial, health care, public safety, emergency response use cases. To fully exploit the potential location awareness enable new advanced location-based services, localization algorithms need to be combined with complementary technologies including accurate height estimation, i.e., three...
This paper describes an algorithm to compute the envelope of a set points in plane, which generates convex or non-convex hulls that represent area occupied by given points.The proposed is based on k-nearest neighbours approach, where value k, only parameter, used control "smoothness" final solution.The obtained results show this able deal with arbitrary sets points, and time polygons increases approximately linearly number points.
Every year, for ten years now, the IPIN competition has aimed at evaluating real-world indoor localisation systems by testing them in a realistic environment, with movement, using EvAAL framework. The provided unique overview of state-of-the-art systems, technologies, and methods positioning navigation purposes. Through fair comparison performance achieved each system, was able to identify most promising approaches pinpoint critical working conditions. In 2020, included 5 diverse off-site...
Research and development around indoor positioning navigation is capturing the attention of an increasing number research groups labs world. Among several techniques being proposed for positioning, solutions based on Wi-Fi fingerprinting are most popular since they exploit existing WLAN infrastructures to support software-only tracking applications. Despite enormous efforts in this domain, despite existence some commercial products fingerprinting, it still difficult compare performance, real...
Fingerprint is one of the most widely used methods for locating devices in indoor wireless environments and we have witnessed emergence several positioning systems aimed based on this approach. However, additional efforts are required order to improve performance these so that applications highly dependent user location can provide better services its users. In work discuss some improvements accuracy fingerprint-based systems. Our algorithm ranks information about a hierarchical way by...
This paper presents the analysis and discussion of off-site localization competition track, which took place during Seventh International Conference on Indoor Positioning Navigation (IPIN 2016). Five international teams proposed different strategies for smartphone-based indoor positioning using same reference data. The competitors were provided with several smartphone-collected signal datasets, some used training (known trajectories), others evaluating (unknown trajectories). permits a...
The development of indoor positioning solutions using smartphones is a growing activity with an enormous potential for everyday life and professional applications. research activities on this topic concentrate the new that are tested in specific environments under their own evaluation metrics. To explore real quality smartphone-based capabilities seamlessly adapting to different scenarios, it needed find fair frameworks. design competitions extensive pre-recorded datasets valid way generate...
IPIN 2019 Competition, sixth in a series of competitions, was held at the CNR Research Area Pisa (IT), integrated into program Conference. It included two on-site real-time Tracks and three off-site Tracks. The four presented this paper were set same environment, made buildings close together for total usable area 1000 m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> outdoors 6000 indoors over floors, with path length exceeding 500 m....
Indoor positioning is a thriving research area which slowly gaining market momentum. Its applications are mostly customised, ad hoc installations; ubiquitous analogous to GNSS for outdoors not available because of the lack generic platforms, widely accepted standards and interoperability protocols. In this context, Positioning Navigation (IPIN) competition only long-term, technically sound initiative monitor state art real systems by measuring their performance in realistic environment. Most...
Unusual changes in the regular daily mobility routine of an elderly person at home can be indicator or early symptom developing health problems. Sensor technology utilised to complement traditional healthcare systems gain a more detailed view when performing everyday tasks. We hypothesise that data collected from low-cost sensors such as presence and occupancy analysed provide insights on habits living alone detect changes. validate this hypothesis by designing system automatically learns...
Wi-Fi fingerprinting is a well-known technique used for indoor positioning. It relies on pattern recognition method that compares the captured operational fingerprint with set of previously collected reference samples (radio map) using similarity function. The matching algorithms suffer from scalability problem in large deployments huge density fingerprints, where number radio map prohibitively large. This paper presents comprehensive comparative study existing methods to reduce complexity...
As the monitoring of carbon dioxide is an important proxy to estimate air quality indoor and outdoor environments, it essential obtain trustful data from CO2 sensors. However, use widely available low-cost sensors may imply lower quality, especially regarding accuracy. This paper proposes a new approach for enhancing accuracy using extremely randomized trees algorithm. It also reports results obtained experimental collected that were exposed both environments. The set was composed two metal...
Maintaining consistent radio maps for WiFi fingerprinting-based indoor positioning systems is an essential step to improve the performance of engines. The consist fingerprints collected at a predefined set positions/places within area. Each fingerprint consists identification and signal level surrounding Access Points (APs). Due wide proliferation networks, it very common observe 10 20 APs single position more than 50 across building. However, in practical, not all detected are useful...
Wi-Fi fingerprinting is widely used for indoor positioning and navigation due to the ubiquity of wireless networks, high proliferation Wi-Fi-enabled mobile devices, its reasonable accuracy. The assumption that position can be estimated based on received signal strength intensity from multiple access points at a given point. accuracy, within few meters, enables use in many different applications. However, it has been detected error might very large cases, which prevent applications with...
This paper presents results from comparing different Wi-Fi fingerprinting algorithms on the same private dataset. The where realized by independent teams in frame of off-site track EvAAL–ETRI Indoor Localization Competition which was part Sixth International Confere nce Positioning and Navigation (IPIN 2015). Competitors designed validated their against publicly available UJIIndoorLoc database contains a huge reference- validation data set. All competing systems were evaluated using mean...
Optical transmission systems are mainly impaired by the shot noise induced ambient light, transmitted optical power limitations (high path losses), channel bandwidth owing to multipath dispersion and interference produced artificial light sources. Several modulation encoding schemes have been proposed for this their performance has studied presented several authors while neglecting effects of interference. The work reported extends previous analysis taking into account penalty An analytical...
Understanding and modeling the way humans move in urban contexts is beneficial for many applications. The recent advances on positioning technologies, namely those based ubiquity of wireless networks, facilitating observation people human motion analysis. In this paper we present result a large scale work conducted to study mobility University's campuses. was along several months, using data collected from thousands users that freely moved inside numerous buildings existent two University...
The accuracy of fingerprinting-based positioning methods is limited by the fluctuations in radio signal intensity mainly due to reflections, refractions, and multipath interference, among other factors. We consider that (often modelled as a Gaussian process for simplification purposes) can be minimized exploiting richness multiple signals collected simultaneously through independent network interfaces. This paper introduces an analysis Wi-Fi signals' statistics using simultaneous...
Wireless indoor infrared transmission systems are affected by noise and interference induced natural artificial ambient light. While the shot on receiver photodiode steady light has been extensively described included in system models, produced only mentioned as a source of degradation quite simple descriptions have presented. This paper presents characterisation (through extensive measurements) proposes model to describe it. These measurements show that can introduce significant in-band...
Purpose This study aims to examine the impact of Russia’s invasion Ukraine on stock prices in energy sector. It analyzes abnormal returns (ARs) sector Europe. Design/methodology/approach uses an event methodology analyze ARs conventional and renewable market indices a large group companies both European sectors. Findings The results show heterogeneous effects. There is positive index, which may be because investors anticipating need for clean energy. Research limitations/implications suggest...