Human Mobility Monitoring using WiFi: Analysis, Modeling, and Applications

Understanding and modeling humans and device mobility has fundamental importance in mobile computing, with implications ranging from network design and location-aware technologies to urban infrastructure planning. Today\u27s users carry a plethora of devices such as smartphones, laptops, tablets, and smartwatches, with each device offering a different set of services resulting in different usage and mobility leading to the research question of understanding and modeling multiple user device trajectories. Additionally, prior research on mobility focuses on outdoor mobility when it is known that users spend 80% of their time indoors resulting in wide gaps in knowledge in the area of indoor mobility of users and devices. Here, I try to fill the gaps in mobility modeling in the areas of understanding and modeling indoor-outdoor human mobility as well as multi-device mobility. In this thesis, I propose the characterization and modeling of human and device mobility. Further, I design and deploy mobility-aware applications for contact tracing of infectious diseases and energy-aware Heating, Ventilation, and Air Conditioning (HVAC) scheduling. I try and answer a sequence of four primary inter-related questions : (1) how is indoor and outdoor user mobility different, (2) are multiple device trajectories belonging to a single user correlated, (3) how to model indoor mobility of users and (4) how to design effective mobility aware applications that are easily deployable and align with long term goals of sustainability as well relay positive societal impact. The insights gained from each question serves as a base to build up on the next question in the series. I present answers to these questions across three main parts of my thesis. The first part comprises of characterization and analysis of human and device mobility. In this part I design and develop tool to extract device trajectories from WiFi system logs syslog and map devices to users. These extracted trajectories and device to user mapping are used to characterize and empirically analyze the mobility of users at varying spatial granularity (indoor, outdoor) and extract device mobility correlations between multiple devices of users and forms the first part of my thesis. In the second part, based on the insights gained from the multi-granular and multi-device mobility characterization stated above, I argue that mobility is inherently hierarchical in nature and propose novel indoor human mobility modeling approach. Third, I leverage the passively observed mobility to design mobility-aware applications that either look back or look ahead in time. WiFiTrace is a look back or backtracking application that is a network-centric contact tracing tool to aid healthcare workers in manual contact tracing of infectious diseases and iSchedule is a look ahead machine learning based mobility-aware energy-saving application that predicts Heating, Ventilation, and Air Conditioning (HVAC) schedule for higher energy savings while increasing user comfort

Outdoor-Indoor tracking systems through geomatic techniques: data analysis for marketing and safety management

Negli ultimi decenni, l'utilizzo di sistemi di gestione delle informazioni nel trattamento dei dati edilizi ha portato a cambiamenti radicali nei metodi di produzione, documentazione e archiviazione dei dati. Dato il crescente interesse per i dati e la loro gestione, l'obiettivo di questa tesi è quello di creare un flusso di lavoro efficace e chiaro a partire dai rilievi geomatici in un'ottica di miglioramento dei dati raccolti sul territorio, sugli edifici circostanti e su quelli relativi al comportamento umano, in modo che possano essere meglio sfruttati e integrati in modelli di gestione intelligenti. Come primo passo, questa tesi mira a comprendere i limiti dell'interoperabilità e dell'integrazione dei dati nei GIS. Per promuovere l'interoperabilità dei dati GIS, è necessario analizzare i metodi di conversione nei diversi modelli di archiviazione dei dati, come CityGML e IndoorGML, definendo un dominio ontologico. Questo ha portato alla creazione di un nuovo modello arricchito, basato sulle connessioni tra i diversi elementi del modello urbano in GIS. Il secondo passo consiste nel raccogliere tutti i dati tradotti in un database a grafo sfruttando il web semantico. Il risultato offrirà vantaggi sostanziali durante l'intero ciclo di vita del progetto. Questa metodologia può essere applicata anche al patrimonio culturale, dove la gestione delle informazioni gioca un ruolo fondamentale. Un altro lavoro di ricerca è stato quello di sviluppare un sistema di gestione SMART per le attività di conservazione dei borghi storici attraverso la gestione di tipologie eterogenee di dati, dal rilievo alla documentazione tecnica. Il flusso di lavoro è stato strutturato come segue: (i) acquisizione dei dati; (ii) modellazione 3D; (iii) modellazione della conoscenza; (iv) modellazione della gestione SMART. Questa ricerca apre la strada allo sviluppo di una piattaforma web in cui importare i dati GIS per un approccio di digital twin. Tutte le ricerche svolte fino a questo punto sono state finalizzate a comprendere la capacità di creare modelli e sistemi informativi intelligenti per capire la fattibilità di ospitare dati eterogenei che potrebbero essere inclusi in futuro. Il passo successivo consiste nel comprendere il comportamento umano in uno spazio. Finora sono pochi i lavori di ricerca che si occupano di sistemi di mappatura e posizionamento che tengono conto sia degli spazi esterni che di quelli interni. Questo argomento, anche se ha pochi articoli di ricerca, rappresenta un aspetto cruciale per molte ragioni, soprattutto quando si tratta di gestire la sicurezza degli edifici danneggiati. Angelats e il suo gruppo di ricerca al CTTC hanno lavorato su questo aspetto, fornendo un sistema in grado di seguire in tempo reale le persone dall'esterno all'interno di spazi chiusi e viceversa. L'uso di sensori GNSS combinato con l'odometria inerziale visiva fornisce una traiettoria continua senza perdere il percorso seguito dall'utente monitorato. Una parte di questa tesi si è concentrata sul miglioramento della traiettoria finale ottenuta con il sistema appena descritto, effettuando test sulla traiettoria esterna del GNSS per capire il comportamento della traiettoria quando si avvicina agli edifici o quando l'utente si sposta in indoor. L'ultimo aspetto su cui si concentrerà la tesi è il tracciamento delle persone in ambienti chiusi. Il comportamento umano è al centro di numerosi studi in diversi campi, come quello scientifico, sociale ed economico. A differenza del precedente caso di studio sul tracciamento delle persone in aree esterne/interne, l'obiettivo è stato quello di raccogliere informazioni sul posizionamento dinamico delle persone in ambienti indoor, sulla base del segnale WiFi. Verrà effettuata una breve analisi dei dati per dimostrare il corretto funzionamento del sistema, per sottolineare l'importanza della conoscenza dei dati e l'uso che se ne può fare.In the last decades, the use of information management systems in the building data processing led to radical changes to the methods of data production, documentation and archiving. Given the ever-increasing interest in data and their management, the aim of this thesis is to create an effective and clear workflow starting from geomatic surveys in a perspective of improving the collected data on the territory, surrounding buildings and those related to human behaviour so they can be better exploited and integrated into smart management models As first step this thesis aims to understand the limits of data interoperability and integration in GIS filed. Before that, the data must be collected as raw data, then processed and interpret in order to obtain information. At the end of this first stage, when the information is well organized and can be well understanded and used it becomes knowledge. To promote the interoperability of GIS data, it is necessary at first to analyse methods of conversion in different data storage models such as CityGML and IndoorGML, defining an ontological domain. This has led to the creation of a new enriched model, based on connections among the different elements of the urban model in GIS environment, and to the possibility to formulate queries based on these relations. The second step consists in collecting all data translated into a specific format that fill a graph database in a semantic web environment, while maintaining those relationships. The outcome will offer substantial benefits during the entire project life cycle. This methodology can also be applied to cultural heritage where the information management plays a key role. Another research work, was to develop a SMART management system for preservation activities of historical villages through the management of heterogeneous types of data, from the survey to the technical documentation. The workflow was structured as follows: (i) Data acquisition; (ii) 3D modelling; (iii) Knowledge modelling; (iv) SMART management modelling. This research paves the way to develop a web platform where GIS data would be imported for a digital twin approach. All the research done up to this point was to understand the capability of creating smart information models and systems in order to understand the feasibility to host heterogeneous data that may be included in the future. The next step consist of understanding human behaviour in a space. So far only a few research papers are addressed towards mapping and positioning systems taking into account both outdoor and indoor spaces. This topic, even though it has few research articles, represents a crucial aspect for many reasons, especially when it comes to safety management of damaged building. Angelats and his research team at CTTC have been working on this aspect providing a system able to track in real time people from outdoor to indoor areas and vice-versa. The use of GNSS sensors combined with Visual Inertial Odometry provide a continuous trajectory without losing the path followed by the monitored user. A part of this thesis focused on enhancing the final trajectory obtained with the described system above, carrying out tests on the outdoor trajectory of GNSS in order to understand behaviour of the trajectory when it gets close to buildings or when the user moves indoor. The last aspect this thesis will focus on is the tracking of people indoor. Human behaviour is at the centre of several studies in different fields such as scientific subjects, social and economics. Differently from the previous case study of tracking people in outdoor/indoor areas, the scope was to collect information about the dynamic indoor positioning of people, based on the WiFi signal. A brief analysis of the data will be made to demonstrate the correct functioning of the system, to emphasise the importance of data knowledge and the use that can be made of it

Proceedings of the 2021 Joint Workshop of Fraunhofer IOSB and Institute for Anthropomatics, Vision and Fusion Laboratory

2021, the annual joint workshop of the Fraunhofer IOSB and KIT IES was hosted at the IOSB in Karlsruhe. For a week from the 2nd to the 6th July the doctoral students extensive reports on the status of their research. The results and ideas presented at the workshop are collected in this book in the form of detailed technical reports

Proceedings of the 2021 Joint Workshop of Fraunhofer IOSB and Institute for Anthropomatics, Vision and Fusion Laboratory

2021, the annual joint workshop of the Fraunhofer IOSB and KIT IES was hosted at the IOSB in Karlsruhe. For a week from the 2nd to the 6th July the doctoral students extensive reports on the status of their research. The results and ideas presented at the workshop are collected in this book in the form of detailed technical reports

Indoor navigation for the visually impaired : enhancements through utilisation of the Internet of Things and deep learning

Wayfinding and navigation are essential aspects of independent living that heavily rely on the sense of vision. Walking in a complex building requires knowing exact location to find a suitable path to the desired destination, avoiding obstacles and monitoring orientation and movement along the route. People who do not have access to sight-dependent information, such as that provided by signage, maps and environmental cues, can encounter challenges in achieving these tasks independently. They can rely on assistance from others or maintain their independence by using assistive technologies and the resources provided by smart environments. Several solutions have adapted technological innovations to combat navigation in an indoor environment over the last few years. However, there remains a significant lack of a complete solution to aid the navigation requirements of visually impaired (VI) people. The use of a single technology cannot provide a solution to fulfil all the navigation difficulties faced. A hybrid solution using Internet of Things (IoT) devices and deep learning techniques to discern the patterns of an indoor environment may help VI people gain confidence to travel independently. This thesis aims to improve the independence and enhance the journey of VI people in an indoor setting with the proposed framework, using a smartphone. The thesis proposes a novel framework, Indoor-Nav, to provide a VI-friendly path to avoid obstacles and predict the user s position. The components include Ortho-PATH, Blue Dot for VI People (BVIP), and a deep learning-based indoor positioning model. The work establishes a novel collision-free pathfinding algorithm, Orth-PATH, to generate a VI-friendly path via sensing a grid-based indoor space. Further, to ensure correct movement, with the use of beacons and a smartphone, BVIP monitors the movements and relative position of the moving user. In dark areas without external devices, the research tests the feasibility of using sensory information from a smartphone with a pre-trained regression-based deep learning model to predict the user s absolute position. The work accomplishes a diverse range of simulations and experiments to confirm the performance and effectiveness of the proposed framework and its components. The results show that Indoor-Nav is the first type of pathfinding algorithm to provide a novel path to reflect the needs of VI people. The approach designs a path alongside walls, avoiding obstacles, and this research benchmarks the approach with other popular pathfinding algorithms. Further, this research develops a smartphone-based application to test the trajectories of a moving user in an indoor environment

'I don't think I ever had food poisoning' : A practice-based approach to understanding foodborne disease that originates in the home

© 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).Food stored, prepared, cooked and eaten at home contributes to foodborne disease which, globally, presents a significant public health burden. The aim of the study reported here was to investigate, analyse and interpret domestic kitchen practices in order to provide fresh insight about how the domestic setting might influence food safety. Using current theories of practice meant the research, which drew on qualitative and ethnographic methods, could investigate people and material things in the domestic kitchen setting whilst taking account of people's actions, values, experiences and beliefs. Data from 20 UK households revealed the extent to which kitchens are used for a range of nonfood related activities and the ways that foodwork extends beyond the boundaries of the kitchen. The youngest children, the oldest adults and the family pets all had agency in the kitchen, which has implications for preventing foodborne disease. What was observed, filmed and photographed was not a single practice but a series of entangled encounters and actions embedded and repeated, often inconsistently, by the individuals involved. Households derived logics and principles about foodwork that represented rules of thumb about 'how things are done' that included using the senses and experiential knowledge when judging whether food is safe to eat. Overall, food safety was subsumed within the practice of 'being' a household and living everyday life in the kitchen. Current theories of practice are an effective way of understanding foodborne disease and offer a novel approach to exploring food safety in the home.Peer reviewedFinal Published versio

Location Privacy in the Era of Big Data and Machine Learning

Location data of individuals is one of the most sensitive sources of information that once revealed to ill-intended individuals or service providers, can cause severe privacy concerns. In this thesis, we aim at preserving the privacy of users in telecommunication networks against untrusted service providers as well as improving their privacy in the publication of location datasets. For improving the location privacy of users in telecommunication networks, we consider the movement of users in trajectories and investigate the threats that the query history may pose on location privacy. We develop an attack model based on the Viterbi algorithm termed as Viterbi attack, which represents a realistic privacy threat in trajectories. Next, we propose a metric called transition entropy that helps to evaluate the performance of dummy generation algorithms, followed by developing a robust dummy generation algorithm that can defend users against the Viterbi attack. We compare and evaluate our proposed algorithm and metric on a publicly available dataset published by Microsoft, i.e., Geolife dataset. For privacy preserving data publishing, an enhanced framework for anonymization of spatio-temporal trajectory datasets termed the machine learning based anonymization (MLA) is proposed. The framework consists of a robust alignment technique and a machine learning approach for clustering datasets. The framework and all the proposed algorithms are applied to the Geolife dataset, which includes GPS logs of over 180 users in Beijing, China

Urban Informatics

This open access book is the first to systematically introduce the principles of urban informatics and its application to every aspect of the city that involves its functioning, control, management, and future planning. It introduces new models and tools being developed to understand and implement these technologies that enable cities to function more efficiently – to become ‘smart’ and ‘sustainable’. The smart city has quickly emerged as computers have become ever smaller to the point where they can be embedded into the very fabric of the city, as well as being central to new ways in which the population can communicate and act. When cities are wired in this way, they have the potential to become sentient and responsive, generating massive streams of ‘big’ data in real time as well as providing immense opportunities for extracting new forms of urban data through crowdsourcing. This book offers a comprehensive review of the methods that form the core of urban informatics from various kinds of urban remote sensing to new approaches to machine learning and statistical modelling. It provides a detailed technical introduction to the wide array of tools information scientists need to develop the key urban analytics that are fundamental to learning about the smart city, and it outlines ways in which these tools can be used to inform design and policy so that cities can become more efficient with a greater concern for environment and equity