Middleware for Mobile Sensing Applications in Urban Environments

Sensor networks represent an attractive tool to observe the physical world. Networks of tiny sensors can be used to detect a fire in a forest, to monitor the level of pollution in a river, or to check on the structural integrity of a bridge. Application-specific deployments of static-sensor networks have been widely investigated. Commonly, these networks involve a centralized data-collection point and no sharing of data outside the organization that owns it. Although this approach can accommodate many application scenarios, it significantly deviates from the pervasive computing vision of ubiquitous sensing where user applications seamlessly access anytime, anywhere data produced by sensors embedded in the surroundings. With the ubiquity and ever-increasing capabilities of mobile devices, urban environments can help give substance to the ubiquitous sensing vision through Urbanets, spontaneously created urban networks. Urbanets consist of mobile multi-sensor devices, such as smart phones and vehicular systems, public sensor networks deployed by municipalities, and individual sensors incorporated in buildings, roads, or daily artifacts. My thesis is that "multi-sensor mobile devices can be successfully programmed to become the underpinning elements of an open, infrastructure-less, distributed sensing platform that can bring sensor data out of their traditional close-loop networks into everyday urban applications". Urbanets can support a variety of services ranging from emergency and surveillance to tourist guidance and entertainment. For instance, cars can be used to provide traffic information services to alert drivers to upcoming traffic jams, and phones to provide shopping recommender services to inform users of special offers at the mall. Urbanets cannot be programmed using traditional distributed computing models, which assume underlying networks with functionally homogeneous nodes, stable configurations, and known delays. Conversely, Urbanets have functionally heterogeneous nodes, volatile configurations, and unknown delays. Instead, solutions developed for sensor networks and mobile ad hoc networks can be leveraged to provide novel architectures that address Urbanet-specific requirements, while providing useful abstractions that hide the network complexity from the programmer. This dissertation presents two middleware architectures that can support mobile sensing applications in Urbanets. Contory offers a declarative programming model that views Urbanets as a distributed sensor database and exposes an SQL-like interface to developers. Context-aware Migratory Services provides a client-server paradigm, where services are capable of migrating to different nodes in the network in order to maintain a continuous and semantically correct interaction with clients. Compared to previous approaches to supporting mobile sensing urban applications, our architectures are entirely distributed and do not assume constant availability of Internet connectivity. In addition, they allow on-demand collection of sensor data with the accuracy and at the frequency required by every application. These architectures have been implemented in Java and tested on smart phones. They have proved successful in supporting several prototype applications and experimental results obtained in ad hoc networks of phones have demonstrated their feasibility with reasonable performance in terms of latency, memory, and energy consumption.

A Decentralized Session Management Framework for Heterogeneous Ad-Hoc and Fixed Networks

Wireless technologies are continuously evolving. Second generation cellular networks have gained worldwide acceptance. Wireless LANs are commonly deployed in corporations or university campuses, and their diffusion in public hotspots is growing. Third generation cellular systems are yet to affirm everywhere; still, there is an impressive amount of research ongoing for deploying beyond 3G systems. These new wireless technologies combine the characteristics of WLAN based and cellular networks to provide increased bandwidth. The common direction where all the efforts in wireless technologies are headed is towards an IP-based communication. Telephony services have been the killer application for cellular systems; their evolution to packet-switched networks is a natural path. Effective IP telephony signaling protocols, such as the Session Initiation Protocol (SIP) and the H 323 protocol are needed to establish IP-based telephony sessions. However, IP telephony is just one service example of IP-based communication. IP-based multimedia sessions are expected to become popular and offer a wider range of communication capabilities than pure telephony. In order to conjoin the advances of the future wireless technologies with the potential of IP-based multimedia communication, the next step would be to obtain ubiquitous communication capabilities. According to this vision, people must be able to communicate also when no support from an infrastructured network is available, needed or desired. In order to achieve ubiquitous communication, end devices must integrate all the capabilities necessary for IP-based distributed and decentralized communication. Such capabilities are currently missing. For example, it is not possible to utilize native IP telephony signaling protocols in a totally decentralized way. This dissertation presents a solution for deploying the SIP protocol in a decentralized fashion without support of infrastructure servers. The proposed solution is mainly designed to fit the needs of decentralized mobile environments, and can be applied to small scale ad-hoc networks or also bigger networks with hundreds of nodes. A framework allowing discovery of SIP users in ad-hoc networks and the establishment of SIP sessions among them, in a fully distributed and secure way, is described and evaluated. Security support allows ad-hoc users to authenticate the sender of a message, and to verify the integrity of a received message. The distributed session management framework has been extended in order to achieve interoperability with the Internet, and the native Internet applications. With limited extensions to the SIP protocol, we have designed and experimentally validated a SIP gateway allowing SIP signaling between ad-hoc networks with private addressing space and native SIP applications in the Internet. The design is completed by an application level relay that permits instant messaging sessions to be established in heterogeneous environments. The resulting framework constitutes a flexible and effective approach for the pervasive deployment of real time applications.

Vision based indoor positioning in a retail environment

Modern smart phones often come with a significant amount of computational power and an integrated digital camera making them an ideal platform for intelligents assistants. This work is restricted to retail environments, where users could be provided with for example navigational in- structions to desired products or information about special offers within their close proximity. This kind of applications usually require information about the user's current location in the domain environment, which in our case corresponds to a retail store. We propose a vision based positioning approach that recognizes products the user's mobile phone's camera is currently pointing at. The products are related to locations within the store, which enables us to locate the user by pointing the mobile phone's camera to a group of products. The first step of our method is to extract meaningful features from digital images. We use the Scale- Invariant Feature Transform SIFT algorithm, which extracts features that are highly distinctive in the sense that they can be correctly matched against a large database of features from many images. We collect a comprehensive set of images from all meaningful locations within our domain and extract the SIFT features from each of these images. As the SIFT features are of high dimensionality and thus comparing individual features is infeasible, we apply the Bags of Keypoints method which creates a generic representation, visual category, from all features extracted from images taken from a specific location. A category for an unseen image can be deduced by extracting the corresponding SIFT features and by choosing the category that best fits the extracted features. We have applied the proposed method within a Finnish supermarket. We consider grocery shelves as categories which is a sufficient level of accuracy to help users navigate or to provide useful information about nearby products. We achieve a 40% accuracy which is quite low for commercial applications while significantly outperforming the random guess baseline. Our results suggest that the accuracy of the classification could be increased with a deeper analysis on the domain and by combining existing positioning methods with ours.

Exploring privacy for ubiquitous computing: Tools, methods and experiments

Ubiquitous computing is about making computers and computerized artefacts a pervasive part of our everyday lifes, bringing more and more activities into the realm of information. The computationalization, informationalization of everyday activities increases not only our reach, efficiency and capabilities but also the amount and kinds of data gathered about us and our activities. In this thesis, I explore how information systems can be constructed so that they handle this personal data in a reasonable manner. The thesis provides two kinds of results: on one hand, tools and methods for both the construction as well as the evaluation of ubiquitous and mobile systems---on the other hand an evaluation of the privacy aspects of a ubiquitous social awareness system. The work emphasises real-world experiments as the most important way to study privacy. Additionally, the state of current information systems as regards data protection is studied. The tools and methods in this thesis consist of three distinct contributions. An algorithm for locationing in cellular networks is proposed that does not require the location information to be revealed beyond the user's terminal. A prototyping platform for the creation of context-aware ubiquitous applications called ContextPhone is described and released as open source. Finally, a set of methodological findings for the use of smartphones in social scientific field research is reported. A central contribution of this thesis are the pragmatic tools that allow other researchers to carry out experiments. The evaluation of the ubiquitous social awareness application ContextContacts covers both the usage of the system in general as well as an analysis of privacy implications. The usage of the system is analyzed in the light of how users make inferences of others based on real-time contextual cues mediated by the system, based on several long-term field studies. The analysis of privacy implications draws together the social psychological theory of self-presentation and research in privacy for ubiquitous computing, deriving a set of design guidelines for such systems. The main findings from these studies can be summarized as follows: The fact that ubiquitous computing systems gather more data about users can be used to not only study the use of such systems in an effort to create better systems but in general to study phenomena previously unstudied, such as the dynamic change of social networks. Systems that let people create new ways of presenting themselves to others can be fun for the users---but the self-presentation requires several thoughtful design decisions that allow the manipulation of the image mediated by the system. Finally, the growing amount of computational resources available to the users can be used to allow them to use the data themselves, rather than just being passive subjects of data gathering.

Internet- karttapalveluiden arviointi ja kehitys strategisessa maankäytön suunnittelussa, tapaustutkimuksena Esikaupunkien renessanssi -hanke

Participation is located in a living and complex environment. Traditional means of participation are only partially able to meet the new environmental requirements. In need are forms of participation which take into account the new opportunities of the environment and residents expertise. Internet map applications are an important channel of participation which potential is in many respects as unexplored and unutilized. They are commonly in inventory the perspectives, bringing out the concerns of the area, and only little for discussing about solutions. Interpretation is usually made by designer. This study focuses on evaluation and development of Internet map applications in strategic land use planning. Subject matter is dealt from designer and the inhabitants point of view. City Planning Department of Helsinki s Esikau-punkien Renessanssi -project and the associated SoftGIS survey acts as the case study. In the beginning of the study I tried to recognize the new environment in which the Internet map applications are placed. The research question is, what kind of challenges and opportunities the e-participation confronts in information society, and what kind of requirements the environmental creates for development of an application. In chapter three I evaluate how successfully these requirements are met in Esikau-punkien Renessanssi -project. I m trying to examine how the application would look like if the environment and the characteristics of the project are met better. The approach is experimental and I try to find new ways to take advantage of Internet maps. I try not to be too limited to current projects and studies. For example, I try to examine how social media and Web 2.0 opportunities can be utilized, and how the learning and shaping nature of planning may be reached in Internet map environment. In chapter four I have developed a new concept for the Esikaupunkien Renessanssi map application, and made images to visualize its operation in practice. I collect all the data in the research and gather it into a new service. The aim is to create a better application for Esikaupunkien Renessanssi -project, which takes into account the living and complex environment of participation and responds to threats and opportunities arising from it. The presented outcome is in many respects different from the current query. In the new service the role of residents is to interact and learn. The traditional standing of the Internet maps and the position of resident as one-sided information donor are questioned. In the concept, the residents innovate and make interpretations too. Influences are taken from a number of modern applications and for example services that make use of social media. The user experience is intended to be interactive, fast and easy. The idea is that the service keeps you up to date with planning matters, not the other way around. Service guides inhabitants, striving to achieve a deeper knowledge of the project's objectives as well as the dynamics and realities that different individuals experience.

Turning the Kaleidoscope - (E)FL Educational Experience and Inquiry as Auto/biography

This book is a study on learning, teaching/counselling, and research on the two. My quest has been to find a pedagogically-motivated way of researching learning and teaching interaction, and in particular counselling, in an autonomous language-learning environment. I have tried to develop a method that would make room for lived experience, meaning-making and narrating, because in my view these all characterise learning encounters between language learners and counsellors, and learners and their peers. Lived experience as a source of meaning, telling and co-telling becomes especially significant when we try to listen to the diverse personal and academic voices of the past as expressed in autobiographical narratives. I have aimed at researching various ALMS dialogues (Autonomous Learning Modules, University of Helsinki Language Centre English course and programme), and autobiographical narratives within them, in a way that shows respect for the participants, and that is relevant, reflective and, most importantly, self-reflexive. My interest has been in autobiographical telling in (E)FL [(English as a) foreign language], both in students first-person written texts on their language- learning histories and in the sharing of stories between learners and a counsellor. I have turned to narrative inquiry in my quest and have written the thesis as an experiential narrative. In particular, I have studied learners and counsellors in one and the same story, as characters in one narrative, in an attempt to avoid the impression that I am telling yet another separate, anecdotal story, retrospectively. Through narrative, I have shed light on the subjective dimensions of language learning and experience, and have come closer to understanding the emotional aspects of learning encounters. I have questioned and rejected a distanced and objective approach to describing learning and teaching/counselling. I have argued for a holistic and experiential approach to (E)FL encounters in which there is a need to see emotion and cognition as intertwined, and thus to appreciate learners and counsellors emotionally-charged experiences as integral to their identities. I have also argued for a way of describing such encounters as they are situated in history, time, autobiography, and the learning context. I have turned my gaze on various constellations of lived experience: the data was collected on various occasions and in various settings during one course and consists of videotaped group sessions, individual counselling sessions between students and their group counsellor, biographic narrative interviews with myself, open-ended personally-inspired reflection texts written by the students about their language-learning histories, and student logs and diaries. I do not consider data collection an unproblematic occasion, or innocent practice, and I defend the integrity of the research process. Research writing cannot be separated from narrative field work and analysing and interpreting the data. The foci in my work have turned to be the following: 1) describing ALMS encounters and specifying their narrative aspects; 2) reconceptualising learner and teacher autonomy in ALMS and in (E)FL; 2) developing (E)FL methodologically through a teacher-researcher s identity work; 4) research writing as a dialogical narrative process, and the thesis as an experiential narrative. Identity and writing as inquiry, and the deeply narrative and autobiographical nature of the (E)FL teaching/counselling/researching have come to the fore in this research. Research writing as a relational activity and its implications for situated ways of knowing and knowledge turned out to be important foci. I have also focussed on the context-bound and local teacher knowledge and ways of knowing about being a teacher, and I have argued for personal ways of knowing about, and learning and studying foreign languages. I discuss research as auto/biography: as a practising counsellor I use my own life and (E)FL experience to understand and interpret the stories of the research participants even though I was not involved in their course work. The supposedly static binaries of learner/teacher, and also learner autonomy/teacher autonomy, are thus brought into the discussion. I have highlighted the infinite variability and ever-changing nature of learning and teaching English, but the book is also of relevance to foreign language education in general.

Psychologically-Based and Content-Oriented Experience in Entertainment Virtual Environments

In daily life, rich experiences evolve in every environmental and social interaction. Because experience has a strong impact on how people behave, scholars in different fields are interested in understanding what constitutes an experience. Yet even if interest in conscious experience is on the increase, there is no consensus on how such experience should be studied. Whatever approach is taken, the subjective and psychologically multidimensional nature of experience should be respected. This study endeavours to understand and evaluate conscious experiences. First I intro-duce a theoretical approach to psychologically-based and content-oriented experience. In the experiential cycle presented here, classical psychology and orienting-environmental content are connected. This generic approach is applicable to any human-environment interaction. Here I apply the approach to entertainment virtual environments (VEs) such as digital games and develop a framework with the potential for studying experiences in VEs. The development of the methodological framework included subjective and objective data from experiences in the Cave Automatic Virtual Environment (CAVE) and with numerous digital games (N=2,414). The final framework consisted of fifteen factor-analytically formed subcomponents of the sense of presence, involvement and flow. Together, these show the multidimensional experiential profile of VEs. The results present general experiential laws of VEs and show that the interface of a VE is related to (physical) presence, which psychologically means attention, perception and the cognitively evaluated realness and spatiality of the VE. The narrative of the VE elicits (social) presence and involvement and affects emotional outcomes. Psychologically, these outcomes are related to social cognition, motivation and emotion. The mechanics of a VE affect the cognitive evaluations and emotional outcomes related to flow. In addition, at the very least, user background, prior experience and use context affect the experiential variation. VEs are part of many peoples lives and many different outcomes are related to them, such as enjoyment, learning and addiction, depending on who is making the evalua-tion. This makes VEs societally important and psychologically fruitful to study. The approach and framework presented here contribute to our understanding of experiences in general and VEs in particular. The research can provide VE developers with a state-of-the art method (www.eveqgp.fi) that can be utilized whenever new product and service concepts are designed, prototyped and tested.