Festa Major de Gràcia

Tour de Suisse

Geneva, Delémont, Basel, Lausanne, Zürich and Sankt Gallen…

Instantiations of UbiComp Bricks

I have been playing around a couple of mobile software instantiating ubicomp brick enabling information ubiquity. The concepts they carry are of interest for the second experiment I am planning.

The Nokia Mobile Web Server is truly groundbreaking. Putting Internet accessible servers (web or others) on mobile devices changes the mobile information flow and is a clear step forward an Internet of things. Contextual data can be both pushed and pulled. [my previous post on this]. Source code is available on sourceforge.

A mobile web site, Netscape Gold era style (right). Mobile Apache Server administration and logs
Jaiku is a real-time “rich presence” mobile phone (S60) applications. The authors mention “Rich presence” as the description of the many relevant things a phone knows about a users. Rich presence on Jaiku includes an IM-style away line, your phone profile (ring volume, vibrate), location (country, city/region, neigborhood), Bluetooth devices around, upcoming calendar events, and the duration how long your phone has been idle. Jaiku integrates “all in one” a couple of location technologies (GPS, GSM, BT) and carries the senses of relative and absolute positioning for location awareness.

A rather poor “reach presence”.

The Kaywa reader reads QR codes and as well as datamatrix. The Kaywa QR code generator allows to create a QR code linked to different content (url, sms, text, phone number). Semacodes and such are leaving the reasearch labs and entering the mobile industry’s near-field communication concepts.

Towards LuxTrace: Using Solar Cells to Measure Distance Indoors

J. Randall, O. Amft, G. Tröster, “Towards LuxTrace : using solar cells to measure distance indoors“, LoCA 2005, T Strang & C. Linnhoff-Popien editors, p.40-51.

A paper on a location system that is based on solar modules for navigation and tracking of humans within a building. The concept, LuxTrace, relies on existing infrastructure and proves to be low cost, low weight, low volume and manufactured to have similar characteristics to everyday clothing. The solar modules are used only to track the intensity of indoor lights as a form of context information.

The authors provide an interesting theoretical framework with 2 papers that were not my radar yet:

On Markov localization:
Fox, D.: Markov Localization: A Probabilistic Framework for Mobile Robot Localization and Navigation. PhD thesis, Institute of Computer Science TU Dreseden Germany (1998)

and some early Hightower work providing a taxonomy of location systems:
Hightower, J., Borriello, G.: A survey and taxonomy of location systems for ubiquitous computing. IEEE Computer, 34(8) (2001) 57–66

Relation to my thesis: One type of alternative location technique (as opposed to the mainstream GPS, RF-based) that could very much fit to very specific environments and scenarios. A must be aware on the way the compute their average distance estimation error (less than 18cm with a confidence of 83%)

Mobile Context Inference Using Low-Cost Sensors

Evan Welbourne, Jonathan Lester, Anthony LaMarca, Gaetano Borriello: Mobile Context Inference Using Low-Cost Sensors. LoCA 2005: 254-263.

This paper reports on the fusion of location and non-location sensors data to leverage the synergy between them to enable a wider variety of high-level mobile context inference. The system senses location with a GSM cell phone and a Wi-Fi enabled mobile device (each running Place Lab), and collects additional sensor data using a sensor board that contains an 3-axis digital accelerometers, barometric pressure, analog visible light phototransistor, digital barometer/temperature, relative humidity, 2-axis digital compass, analog electric microphone. The authors show that like previous systems, their system can classify a mode of transit and extract significant places within a user’s daily movements. However, their can do it without the use of GPS (unlike other experiments) and can classify places based on the activity that occurs there.

In Section 3, the authors mention the “experience sampling method” (ESM). After checking Context-Aware Experience Sampling Tool, it appears that in ESM:

Subjects are asked to carry a beeper device that signals on a time-based protocol determined by the researcher. Each time the beeper activates, subjects fill out a survey that typically includes questions asking what the subject was doing and how the subject was feeling at the time of the alarm. With a sufficient number of subjects and samples, a statistical model of activities can be generated. ESM is less susceptible to subject recall errors than other self-report feedback elicitation methods.

Future work in the fuse of location and activity and in mobile context inference include:

• infer the mode of transit to select an appropriate motion model for a location particle filter and improve the location accuracy
• work with place and indoor activity (e.g. mobile place such as bus and train)
• Collect users daily life data and annoted them with the ESM. It could be used to study the effects of place and activity on interruptability and prompting.

Relation to my thesis: It is an example of the fusion of location and non-location sensors to frame the activity of users. I am involved in a project using ESM and might inspire from it for my second experiment.

A Wearable Interface for Topological Mapping and Localization in Indoor Environments

G. Schindler, T. Starner, and C. Metzger. A Wearable Interface for Topological Mapping and Localization in Indoor Environments. 2nd International Workshop on Location and Context-Awareness (LoCA), 2006.

The authors present a method for mapping and localization in indoor environments using FreeDigiter, an ear-mounted gesture interface equipped with an infrared proximity sensor (to detect footsteps, doorways and finger gesture) and a dual axis accelerometer. The mobile robotics community has studied the automatic mapping of unknown indoor environments. Normally, in location-recognition works with wearable accelerometers a dead reckoning approach is used. The accelerometers data are integrated over time to build a metric map of a user’s path through an environment. FreeDigiter also takes the user’s steps, but also captures the connectivity of an indoor environment composed of multiple rooms. It builds and tracks a topological map. In robotics literature focuses on Simultaneous Location And Mapping (SLAM). In their projects, the authors propose a cheap, lightweight device requiring minimal user intervention.

Mapping and localization is done by first building an augmented topological map:

A map is represented as a set of edges E and vertices V defining a graph G = {E, V }. Each edge is augmented with a length l (in footsteps) and an edge-specific probability distribution over proximity sensor readings (the mean μ and variance σ of a Gaussian). By this definition, each edge corresponds to a constant part of the environment – i.e. the world looks the same to the sensors at every point on an edge.

In the building, the proximity sensor is used to detect and measure doorways and use an accelerometer to determine the distance between doorways. Once the map is constructed, the autors used a particle filter to track the user’s movements accross the edges of the graphs. With an experience FreeDigit user tracking accuracy reach 100%. This means a user has to be able to maintain a constant speed and be a consistent walker.

Relation to my thesis: A lab experiment using mapping and localization for person tracking in unknown indoor settings. The authors the knowledge in robotics to person tracking. It is not a surprise to see that somehow the users must behave like robots (keep pace and consistent) for the system to be performant (adding more sensors can alleviate the problem). However, I find interesting that the user takes part of the mapping and trains the location application. The user helps disambiguates. I was not aware of SLAM and might find there some relations between robot and person localization and it provides good reference in robotics localization:

On partical filtering:
S. Thrun, D. Fox, F. Dellaert, and W. Burgard. Particle filters for mobile robot localization. In Arnaud Doucet, Nando de Freitas, and Neil Gordon, editors, Sequential Monte Carlo Methods in Practice. Springer-Verlag, New York, January 2001.

On Voronoi tracking
L.Liao, D.Fox, J.Hightower, H.Kautz, and D.Schulz. Voronoi tracking: Location estimation using sparse and noisy sensor data. In IROS, 2003.

Coping with Uncertainty: Insights from the New Sciences of Chaos, Self-Organization, and Complexity

Coping with Uncertainty: Insights from the New Sciences of Chaos, Self-Organization, and Complexity, by Uri Merry.

The ground hypothesis of this book is that the world becomes more complex and therefore more uncertain. Uri Merry takes the perspective of the new sciences of chaos, self-organization, complexity to understand the impact on individuals and social organizations (families, societies, cities, nations, institutions).

Chaos is the time of transition between orders (transition period). It is the irregular, uncertain, discontinuous aspect of change within the confines of a patterned whole. Chaos creates stress in human life; when too many uncertainties engult a person, he or she may become stressed. The uncertain and unpredictable forms of change are in contrast to the regular and predictable ways people expect and believe that most things around them do change. People build organizations as a line of defense against the uncertainty and the chaotic elements of the world. It allows them to define regularity, predictability, routines, norms, rules and roles to reach stability and defense against uncertainty. Nevertheless, a mixture of order and chaos is the natural form of all living things. Indeed, uncertainty, unpredictability, complexity and chaos are a natural legitimate necessary, inescapable aspect of reality and will never go away.

Complex behaviors may emerge from a number of basic rules controlling part of the system. That behaviors is not predictable from knowledge of the individual elements. But it can be discovered by studying how the elements interact and how the system is and changes throughout time. The features distinguishing complext systems (p. 59) are: non-reducibility, emergent behavior, unpredictability and regularity.

The more complex a system becomes, the greater it needs to become aware of and devote communication information resources, and interaction skills to maintain its internal processes. Prigogine and Stengers describe this as a competition between communication and fluctuations. “There is competition between stabilization though communication and instability through fluctuations. The outcome of that competition determines the threshold of stability“. (p. 65) Moreover, increase connectedness leads to complexity. That is increased interdependence intensifies uncertainty if the quality of the relationships does not match the degree of interdependence. Eventually, the more complex, the more likely to break.

P. 81-82 contain a few line on technology as an intensifier of uncertainty in the world. Ironically, we develop technologies to regain control (stability), while technology accelerates changes and therefore feeds the complexity spiral.

Individuals, organizations, and societies react to uncertainty engendered by basic change in a number of ways (p. 123):

• Repeating former behavior over and over again
• Varying behavior slightly and predictably
• Adapting new behaviors
• Transiting through a choatic crisis
• Transforming to a new more complex mode of functioning

Most people will not make a deeper kind of change if they can get by with a lighter change. They will first tend to try out behavior they are user to and create variations if circumstances demand it.

Accepting Uncertainty (p. 143)
The ability to accept uncertainty and tolerate ambiguity might become an essential aspect of a personality that has to deal with an unpredictable environment. Accepting uncertainty includes the ability to be in confusion and to accept that confusion as a necessary element in the process of interacting with a nonlinear world, a world suffused with ambiguity. Ambiguity being uncertainty of meaning.

Boundaries are not clear and objects can be viewd and understood from multiple viewpoints wihtout one canceling the other out. Accepting uncertainty necessitates an ability to live with ambivalence such as having both negative and positive sentiments with regard to the same object. Ambivalence is uncertainty of value.

An uncertain, unpredictable environment is one to which a person must constantly find a fit.

Awareness (p. 151)
An environment of turbulence and discontinuous change may necessitate functioning at a higher level of awareness. Humans may need to accustom themselves to everyday functioning at a level of consciousness that is suited to an uncertain environment. This would necessitate their being able to maintain a state of consciousness of being fully aware of what they are engaged in within the environment together with a hold on their self as the focal point from which to decide in what to engage. Being fully aware entails maintaining consciousness focus awaringly in two directions simultaneously: on what one is engaged in with the environment and on the self that is observing the activity.

P. 173 has a few words on coevolution as well as competition and cooperation.

Designing and Developing Systems (p. 192)
Evolutionary system design attempts to translate the vision into policies and activities that advance human systems closer to their vision. In system design, pieces cannot be broken off to be dealt with separately. The quality of the part is dependent on its relationship to the whole. The design needs to focus on interactions and interrelations of all the components of the system. The system must be designed as a whole. While there will be differences, there may be a number of guidelines that can assist those attempting to create a design and develop it:

• Balancing at the edge of chaos
• Creating and identity of a learning system
• Taking a coherent part in the network of ecological processes. Encouraging variety and diversity
• Learning to manage chaos
• Coevolvement of the outer and the inner world.

Relation to my thesis: ubiquitous computing is about complexity, unpredictability, stability, consistency, robustness, fluctuancy, vulnerability, resilience, irregularity, ambiguity, uncertaitny, ambivalence, and confusion. All these words have been used in this books and are related to the problem I would like to solve. I should probably find a clear definition of each of these terms and link them to my current topology of spatial uncertainty. Ubiquitous computing is also challenged by the nonlinear and interdependent human and social systems. The world has inherent irregularity (nonlinear world). System designer must accept uncertainty in an unpredictable environment. The author mention the necessity of awareness of complexity and explained it as “stability through communication”. It stays very abstract, but I surely could inspire from it. Also inspiring are the categories of reaction to uncertainty engerered by basic change.

On a more philosophical level, I could use the “technology as an intensifier of uncertainty” as introduction to my work. Somehow play with the irony to we develop technology for the opposite purpose. It has some similarities with what Satyanarayanan (2003) was writting in his “Coping with Uncertainty“. That is that digital computing allowed us to eliminate uncertainty with finite state representation and transformation. And now ironic that today’s all-digital world, uncertainty reappears as a major concern at a higher level of representation.

Point and Retrieve

Two services of “point and retrieve” have been announced almost simultaneously. iPointer and GeoVector (NYT article) are based on a GPS-enabled mobile phone with an embedded digital magnetic compass and a wireless data connection. They allow to retrieve information about a landmark by pointing at it:

When users wish to identify a landmark, they point the hand-held device and press a button. The iPointer™ device receives coordinate signals from GPS satellites and orientation information from the digital magnetic compass to identify the user’s location and device’s pointing angle. These coordinates are then sent over the wireless network to the database. iST’s geospatial database’s selection algorithms identify the selected landmark and sends information back over the wireless network to be displayed in text, visuals and audio on the user’s device.

Relation to my thesis: A technology that enables near field interaction with the physical space and local search. I am absolutly curious to know how users of such services manage the shortcoming of the technology. Does a magnetic compas increases or decreases confusion in navigating in urban environments?

Comment Faire de la Recherche en Intelligence Artificielle

Jacques Pitrat, Comment faire de la recherche en intelligence artificielle, LAFORIA 97/06. Mars 1997

Ce papier donne quelques conseils au chercheur qui commence une thèse en intelligence artificielle basées sur le développement d’un système utilisant l’informatique. Il dégage certains points communs avec ma recherche appliquée en HCI/UbiComp.

Tout d’abord une étude d’IA devrait comporter la réalisation de deux systèmes. Le premier pour se familiariser avec le domaine et ses difficultés, sans attendre des résultats extraordinaires. Après une péridoe de plusieurs mois de décantation (écriture de papier décrivant ce qui a été fait), vient la mise en place du deuxième système, tenant compte des enseignements de la première expérimentation, qui apportera des idées vraiment nouvelles. C’est ce que je tente d’effectuer avec d’abord CatchBob! puis système possiblement un système dans le zone 22@ à Barcelone.

Deux chercheurs peuvent faire davantage de travail qu’un seul, et cela permet de s’attaquer à des problèmes qui demandent la résolution de plusieurs difficultés, chaque chercheur prenant en charge l’une d’entre elle. Je le fais déjà avec Nicolas. Thème abordé à mon dernier meeting.

Il faut savoir aller à l’opposé avec ce qu’enseignent les informaticiens. C’est-à-dire commencer à réaliser un système alors que l’on ne sait pas bien ce que l’on va y mettre (dans mon cas, faire du participatory design). Il se trouve qu’en IA la situation est en général tellement complexe qu’il est impossible de faire une analyse préalable.

Mettre son inconscient dans de bonnes conditions pour travailler. C’est-à-dire lire ce qui a été fait dans le domaine et dans d’autres domaines (trouver des analogies). Ce que je fais en aller gratter dans la géographie, psychology (spatil cognition and navigation), information retrieval, systémique et robotics. Il n’est pas bon de travailler de façon continue. Les repos permettent de digérer et d’assimiler ce qui vient d’être fait. Mélanger des travaux moins prenants aux périodes de réfléxion (littérature, rédaction).

La chronologie de la thèse peut être définie comme suit: Toute une année peut être nécessaire pour définir un sujet satisfaisant et voir comment bâtir un système capable de résoudre les problèmes qu’ils veulent lui poser. Puis la phase de réalisation et expérimentation du système est d’au moins deux ans. Il faut compter trois ans pour la réalisation d’une thèse dès lors qu’elle comporte l’expérimentation d’un système, en supposant que les trois quart du temps y sont consacré. Un pré-soutenance au bout des premières années de thèse est une bonne idée (c’est qui sera le cas pour moi avec l’obtention d’un DEA après 2 ans de PhD). C’est l’occasion de rédiger une description de l’ensemble de ce qui a été fait et de faire apparaître des insuffisancces.

Relation to my thesis: learning while doing

Real-World Deployments Theme in IEEE Pervasive Computing Journal

Current IEEE Pervasive Computing Journal issue (July-September 2006 (Vol. 5, No. 3)) features papers on real-world deployment of pervasive systems. Contributions close to my focus are:

Albrecht Schmidt, Sarah Spiekermann, Anatole Gershman, Florian Michahelles, “Real-World Challenges of Pervasive Computing,” IEEE Pervasive Computing, vol. 5, no. 3, pp. 91-93, c3, Jul-Sept, 2006.

Jeffrey Hightower, Anthony LaMarca, Ian E. Smith, “Practical Lessons from Place Lab,” IEEE Pervasive Computing, vol. 5, no. 3, pp. 32-39, Jul-Sept, 2006.

Thomas Riisgaard Hansen, Jakob E. Bardram, Mads Soegaard, “Moving Out of the Lab: Deploying Pervasive Technologies in a Hospital,” IEEE Pervasive Computing,

Zhiwen Yu, Xingshe Zhou, Daqing Zhang, Chung-Yau Chin, Xiaohang Wang, Ji Men, “Supporting Context-Aware Media Recommendations for Smart Phones,” IEEE Pervasive Computing, vol. 5, no. 3, pp. 68-75, Jul-Sept, 2006.

Oliver Storz, Adrian Friday, Nigel Davies, Joe Finney, Corina Sas, Jennifer Sheridan, “Public Ubiquitous Computing Systems: Lessons from the e-Campus Display Deployments,” IEEE Pervasive Computing, vol. 5, no. 3, pp. 40-47, Jul-Sept, 2006.

Relation to my thesis: I still plan to write a paper on the experience of designing and deploying CatchBob! Real-world experiments is the only way to experiment with problems of scale in uncertain and dynamic environments. As this issue’s editor, Roy Want of Intel, puts it in Build What You Use:

To prove success in ubiquitous computing research, you must implement your ideas and deploy them in support of a work practice or community activity. Anything less, and the design’s utility will always be doubted, even if the core engineering is outstanding.