EAGLE—A Scalable Query Processing Engine for Linked Sensor Data

Recently, many approaches have been proposed to manage sensor data using semantic web technologies for effective heterogeneous data integration. However, our empirical observations revealed that these solutions primarily focused on semantic relationships and unfortunately paid less attention to spatio–temporal correlations. Most semantic approaches do not have spatio–temporal support. Some of them have attempted to provide full spatio–temporal support, but have poor performance for complex spatio–temporal aggregate queries. In addition, while the volume of sensor data is rapidly growing, the challenge of querying and managing the massive volumes of data generated by sensing devices still remains unsolved. In this article, we introduce EAGLE, a spatio–temporal query engine for querying sensor data based on the linked data model. The ultimate goal of EAGLE is to provide an elastic and scalable system which allows fast searching and analysis with respect to the relationships of space, time and semantics in sensor data. We also extend SPARQL with a set of new query operators in order to support spatio–temporal computing in the linked sensor data context.EC/H2020/732679/EU/ACTivating InnoVative IoT smart living environments for AGEing well/ACTIVAGEEC/H2020/661180/EU/A Scalable and Elastic Platform for Near-Realtime Analytics for The Graph of Everything/SMARTE

The Design and Use of a Smartphone Data Collection Tool and Accompanying Configuration Language

Understanding human behaviour is key to understanding the spread of epidemics, habit dispersion, and the efficacy of health interventions. Investigation into the patterns of and drivers for human behaviour has often been facilitated by paper tools such as surveys, journals, and diaries. These tools have drawbacks in that they can be forgotten, go unfilled, and depend on often unreliable human memories. Researcher-driven data collection mechanisms, such as interviews and direct observation, alleviate some of these problems while introducing others, such as bias and observer effects. In response to this, technological means such as special-purpose data collection hardware, wireless sensor networks, and apps for smart devices have been built to collect behavioural data. These technologies further reduce the problems experienced by more traditional behavioural research tools, but often experience problems of reliability, generality, extensibility, and ease of configuration. This document details the construction of a smartphone-based app designed to collect data on human behaviour such that the difficulties of traditional tools are alleviated while still addressing the problems faced by modern supplemental technology. I describe the app's main data collection engine and its construction, architecture, reliability, generality, and extensibility, as well as the programming language developed to configure it and its feature set. To demonstrate the utility of the tool and its configuration language, I describe how they have been used to collect data in the field. Specifically, eleven case studies are presented in which the tool's architecture, flexibility, generality, extensibility, modularity, and ease of configuration have been exploited to facilitate a variety of behavioural monitoring endeavours. I further explain how the engine performs data collection, the major abstractions it employs, how its design and the development techniques used ensure ongoing reliability, and how the engine and its configuration language could be extended in the future to facilitate a greater range of experiments that require behavioural data to be collected. Finally, features and modules of the engine's encompassing system, iEpi, are presented that have not otherwise been documented to give the reader an understanding of where the work fits into the larger data collection and processing endeavour that spawned it

LifeLogging: personal big data

We have recently observed a convergence of technologies to foster the emergence of lifelogging as a mainstream activity. Computer storage has become significantly cheaper, and advancements in sensing technology allows for the efficient sensing of personal activities, locations and the environment. This is best seen in the growing popularity of the quantified self movement, in which life activities are tracked using wearable sensors in the hope of better understanding human performance in a variety of tasks. This review aims to provide a comprehensive summary of lifelogging, to cover its research history, current technologies, and applications. Thus far, most of the lifelogging research has focused predominantly on visual lifelogging in order to capture life details of life activities, hence we maintain this focus in this review. However, we also reflect on the challenges lifelogging poses to an information retrieval scientist. This review is a suitable reference for those seeking a information retrieval scientist’s perspective on lifelogging and the quantified self

Scalable and Energy Efficient Software Architecture for Human Behavioral Measurements

Understanding human behavior is central to many professions including engineering, health and the social sciences, and has typically been measured through surveys, direct observation and interviews. However, these methods are known to have drawbacks, including bias, problems with recall accuracy, and low temporal fidelity. Modern mobile phones have a variety of sensors that can be used to find activity patterns and infer the underlying human behaviors, placing a heavy load on the phone's battery. Social science researchers hoping to leverage this new technology must carefully balance the fidelity of the data with the cost in phone performance. Crucially, many of the data collected are of limited utility because they are redundant or unnecessary for a particular study question. Previous researchers have attempted to address this problem by modifying the measurement schedule based on sensed context, but a complete solution remains elusive. In the approach described here, measurement is made contingent on sensed context and measurement objectives through extensions to a configuration language, allowing significant improvement to flexibility and reliability. Empirical studies indicate a significant improvement in energy efficiency with acceptable losses in data fidelity

Online network intrusion detection system using temporal logic and stream data processing

These days, the world are becoming more interconnected, and the Internet has dominated the ways to communicate or to do business. Network security measures must be taken to protect the organization environment. Among these security measures are the intrusion detection systems. These systems aim to detect the actions that attempt to compromise the confidentiality, availability, and integrity of a resource by monitoring the events occurring in computer systems and/or networks. The increasing amounts of data that are transmitted at higher and higher speed networks created a challenging problem for the current intrusion detection systems. Once the traffic exceeds the operational boundaries of these systems, packets are dropped. This means that some attacks will not be detected. In this thesis, we propose developing an online network based intrusion detection system by the combined use of temporal logic and stream data processing. Temporal Logic formalisms allow us to represent attack patterns or normal behaviour. Stream data processing is a recent database technology applied to flows of data. It is designed with high performance features for data intensive applications processing. In this work we develop a system where temporal logic specifications are automatically translated into stream queries that run on the stream database server and are continuously evaluated against the traffic to detect intrusions. The experimental results show that this combination was efficient in using the resources of the running machines and was able to detect all the attacks in the test data. Additionally, the proposed solution provides a concise and unambiguous way to formally represent attack signatures and it is extensible allowing attacks to be added. Also, it is scalable as the system can benefit from using more CPUs and additional memory on the same machine, or using distributed servers

Contribution to improve mobility uses through context-awareness

Dey, in his paper “Towards a Better Understanding of Context and Context-Awareness”, argues that context-awareness is important in applications in which the user’s context changes rapidly, such as in mobile environments for ubiquitous computing. In his paper, Dey defines context as “any information that can be used to characterize the situation of an entity”. In mobile environments, the entity is the mobile device itself. The device is both pervasive and person-­centric; it can continuously capture information about its users and their context through its sensors. The use of context has gained importance in ubiquitous computing since the 1990s, and the technique has recently been used in mobile devices to improve their uses and applications. For mobile context-awareness to become a reality, further research is required, particularly in the field of context prediction, which can expand the possibilities of context-awareness applications by expanding the applications’ situation awareness. In this PhD dissertation, we focus on the use of data obtained through mobile device sensors and user behavior to derive and predict context to improve mobility for both the users’ experience and for the applications’ functionality. We contribute to context-­aware mobile computing by showing how mobile devices can automatically learn from the user’s context and can adapt to improve the mobile experience. We begin our work with a state-­‐of-­‐the-­‐art analysis of “context-awareness” proposals for mobile systems and applications and of the current tools used to infer context from the existing environmental variables. In this dissertation, we analyze the existing gaps in mobile environments and propose solutions to resolve these issues. We first define “context-­awareness” and propose an architecture to predict context from a mobility perspective. Numerous definitions of context, context-­awareness and architectures exist, but few focus exclusively on mobility. Moreover, all of the definitions are oriented towards context inference rather than towards a prediction of future context. We develop a model that captures, processes and unifies variables from heterogeneous sources for use by a machine-­learning algorithm that infers and predicts the context. We also test and benchmark several machine-­learning algorithms in our architecture so that we can recommend those algorithms that we consider most appropriate for inferring context in mobility environments. We propose the combination of on-­‐line prediction algorithms and classifier algorithms to enhance context derivation with future context prediction. We evaluate our proposal utilizing real data from the Reality Mining project, which captures data from the daily mobile usage of c.100 Nokia smart phones during an academic year. We conclude with an example of how to apply our proposed architecture and model, and we demonstrate its enrichment of the search experience with a mobile device by including a “context-awareness” module in mobile search engines. We use Bing as the search engine for all of our search examples. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Describe Dey, en su artículo “Towards a Better Understanding of Context and Context-Awareness” cómo la percepción del contexto (context-awareness) cobra importancia en las aplicaciones en las que el contexto del usuario cambia con rapidez, como es el caso en los entornos móviles de la computación ubicua. Dey, en su artículo, define contexto como “cualquier información que pueda usarse para caracterizar la situación de una entidad”. En entornos móviles, dicha entidad es el dispositivo móvil en sí mismo. Este aparato, al ser ubicuo y centrado en las personas, puede captar continuamente información tanto de los usuarios como de su contexto a través de sus sensores. El uso del contexto ha cobrado importancia en entornos de computación ubicua desde la década de los 90, y esta técnica se ha empleado en dispositivos móviles para mejorar su utilización y aplicación. Para que el área de percepción de contexto se convierta en una realidad, se necesita más investigación, sobre todo en el área de predicción de contexto que amplíe las posibilidades de las aplicaciones que usan información de su contexto. En esta tesis doctoral, nos centramos en el uso de los datos obtenidos de los sensores del móvil y en el comportamiento del usuario, para deducir el contexto presente predecir el contexto futuro, mejorando así la usabilidad del móvil y las funcionalidades de sus aplicaciones. Contribuimos a la computación de percepción del contexto móvil demostrando cómo los dispositivos móviles pueden aprender automáticamente sobre el contexto en el que está el usuario y adaptarse al mismo para mejorar la experiencia de movilidad. Comenzamos nuestro trabajo realizando un estudio del estado del arte de propuestas de percepción de contexto para sistemas y aplicaciones móviles, así como de las herramientas para intuir el contexto a partir de variables existentes del entorno. Analizamos las carencias que tienen en su aplicación al área de la movilidad y hacemos propuestas de cómo resolverlas a lo largo de la tesis. Primero sentamos las bases de la tesis definiendo el concepto de percepción de contexto (“context-awarenes”) y realizamos una propuesta de arquitectura de derivación del contexto actual y predicción del contexto futuro desde un punto de vista de un entorno móvil. Existen muchas definiciones de contexto, percepción de contexto y arquitecturas, pero hay pocas orientadas exclusivamente a movilidad. Además todas se centran en la derivación del contexto actual en vez de hacerlo en la predicción del contexto futuro. Desarrollamos un modelo que nos permite captar, procesar y unificar variables de fuentes heterogéneas para que puedan ser utilizadas por el algoritmo de aprendizaje automático para intuir y predecir contexto. También probamos y referenciamos varios algoritmos de aprendizaje automático para poder recomendar los algoritmos que consideramos más apropiados para intuir contexto en entornos de movilidad. Hacemos una propuesta de mejora en la que combinamos los algoritmos de predicción en línea con los algoritmos de clasificación para poder así predecir el contexto futuro además del contexto actual intuido por el clasificador. Evaluamos nuestra propuesta con datos reales de uso del móvil disponibles en el proyecto “Reality Mining”, en el cual se captan datos de uso diario de móviles de aproximadamente 100 Smartphones Nokia usados por estudiantes universitarios durante un año académico. Finalmente concluimos dando un ejemplo de cómo aplicar nuestra arquitectura y el modelo propuesto demostrando como enriquece la experiencia de búsqueda en un dispositivo móvil el hecho de incluir un módulo de percepción de contexto en los buscadores móviles. Usamos el buscador Bing para todos los ejemplos de búsquedas

Using Physical and Social Sensors in Real-Time Data Streaming for Natural Hazard Monitoring and Response

Technological breakthroughs in computing over the last few decades have resulted in important advances in natural hazards analysis. In particular, integration of a wide variety of information sources, including observations from spatially-referenced physical sensors and new social media sources, enables better estimates of real-time hazard. The main goal of this work is to utilize innovative streaming algorithms for improved real-time seismic hazard analysis by integrating different data sources and processing tools into cloud applications. In streaming algorithms, a sequence of items from physical and social sensors can be processed in as little as one pass with no need to store the data locally. Massive data volumes can be analyzed in near-real time with reasonable limits on storage space, an important advantage for natural hazard analysis. Seismic hazard maps are used by policymakers to set earthquake resistant construction standards, by insurance companies to set insurance rates and by civil engineers to estimate stability and damage potential. This research first focuses on improving probabilistic seismic hazard map production. The result is a series of maps for different frequency bands at significantly increased resolution with much lower latency time that includes a range of high-resolution sensitivity tests. Second, a method is developed for real-time earthquake intensity estimation using joint streaming analysis from physical and social sensors. Automatically calculated intensity estimates from physical sensors such as seismometers use empirical relationships between ground motion and intensity, while those from social sensors employ questionaries that evaluate ground shaking levels based on personal observations. Neither is always sufficiently precise and/or timely. Results demonstrate that joint processing can significantly reduce the response time to a damaging earthquake and estimate preliminary intensity levels during the first ten minutes after an event. The combination of social media and network sensor data, in conjunction with innovative computing algorithms, provides a new paradigm for real-time earthquake detection, facilitating rapid and inexpensive risk reduction. In particular, streaming algorithms are an efficient method that addresses three major problems in hazard estimation by improving resolution, decreasing processing latency to near real-time standards and providing more accurate results through the integration of multiple data sets