Lately, I have been thinking about this concept of location-based reminders (LBR). The idea is quite simple. a classical reminder is usually defined for a certain time, while a LBR is defined for a certain place. Setting a LBR opens a whole range of new possibilities as we can combine space and time in different manners to accommodate different behaviors (e.g., being reminded to buy milk while close to the grocery store but only on friday and sunday morning). I remember several projects done in the past that should have achieved exactly this point, like DeDe. However, they all failed because people are uncertain about their spatio-temporal patterns when communicating with other friends.
More specifically, the value of LBR is related to the fact of being reminded while being on the place. However the caveat is that either we are certain about our path in the city, in which case the value of the LBR is reduced, either we are uncertain about the path, the value of the LBR stays high but we can find ourself at home without milk.
Defining a spatio-temporal pattern is not a trivial task. Learning meaningful location is the first step but it is certainly not the added value of the application.
Reading one of the comics I like the best, Nathan Never, I learned an interesting German word: “alterszorn”. It means the ‘rage of age’, and refers to the habit of some older people to go over the polemical edge. The word was used by John le Carré, a British spy-novelist. Contrary to those that with older age become conservatives, calm, and in favor of the status quo, John le Carré took the inverse path because book after book he took a critical attitude towards people in charge, e.g., politicians, and their ability to manipulate, and falsify. This becomes more visible in one of his last books: Absolute friends.
I hope I will get alterszorn when I will more mature …
The other day, I had a nice chat with Paolo on the science behind these products that shields electro-magnetic (EM) waves. He recalled the formula that is used to calculate the skin depth of a conducting material in order to understand whether a certain EM signal can penetrate it or not.
An electromagnetic wave entering a conducting surface is damped and reduces in amplitude by a factor 1/e in a distance ∂ given by:
where ω is the angular frequency of the radiation and σ the electrical conductivity of the metal. This distance is referred to as the skin depth of the conductor. The effect is caused by electromagnetic induction in the metal which opposes the currents set up by the wave E-field, and holds for oscillations below about 1012 Hz.
Sunday night I enjoyed an edition of Report, an Italian TV show, which presented a translated edition of Paul Kenyon’s “WiFi: a warning signal”, a BBC show. Kenyon’s thesis was straight forward: we know little about the biological effects of electromagnetic fields (RF). Studies reported controversial findings on the issue. In this situation we should adopt a precautionary approach against radio technologies. I fully agree with this thesis, full stop.
In this post I am not going into the debate of the scientific evidences in favor or against the bio-effects of RF. I simply accept that we do not know enough and the we should be cautious. My point is that radio signals are all around us and it is almost impossible to protect ourself from this electrosmog, or is it?As I studied environmental protection in my high-school degree, I believe we should follow some simple guidelines to reduce exposure to radio waves. To be more precise, we should reduce the dose of electromagnetic energy that we receive each day.
Some simple things that we can do at no cost:
- Turn off unused electric/electronic appliances (standby mode is not good);
- Place cordless phones and its base station far from bedrooms (especially DECT phones);
- Turn off the WiFi router when unused and during night time;
- Do not keep the mobile phone in the pocket when we are indoor (we can place it at a arm’s reach when we are home or in the office);
- …
Ok, fine, I can turn off the WiFi antenna, but what about the neighbor’s antenna, which is always on? And what about the GSM mast tower sitting 100 meters from my bedroom’s window? Well, in this case things are slightly more complicated. But still there are shielding solutions that we can put in place. In particular there are metallic nets and sheets that we can put on the walls that reduce substantially the signal strength of the microwaves reaching our appartment. The caveat is that these layers needs to be grounded with proper wiring otherwise they accumulate static energy and they loose their beneficial effect.
Also, there exist a carbonic paint for the walls that has a shielding effect. It is called Yschield, produced by a German company.
In summary, while we wait for a definite answer on the biological effects of these radio-waves, we better be cautious and reduce the amount of RF energy that our body takes each day. Just in case
Back in Florence, at CHI2008, I attended an interesting presentation of Tovi Grossman (DGP, University of Toronto), on volumetric displays. A volumetric display is a graphical device that forms a visual representation of an object in three physical dimensions, as opposed to the planar image of traditional screens that simulate depth through a number of different visual effects. The model he presented, in fact, used a fast-turning mirrors over which an image was projected thus giving a full sense of depth.
Tovi’s PhD thesis inquired how to interact with volumetric displays. Tovi and colleagues designed techniques for selection and interaction with 3D models represented through these displays. Their approach consisted in tracking the hands of the users and the users body using infrared markers and simple video analysis techniques. Volumetric displays are limited because they do not allow deictic gestures on the surface of the model.
The paper that he presented at CHI08 suggest different techniques that can help to overcome this limitation. For instance he suggest the possibility of using a spherical highlighter: a semi-transparent sphere that can be used to highlight a certain part of the model. Different colors can be used by different users. The access control to the view and feature of the drawing raises also interesting questions on how to grant equal participation to two or more users. Their idea, to this end, was that of splitting the drawing in two each sub-model could then be controlled by a single user. Of course, the natural extension of this system is the support of remote collaboration. However, Tovi’s thesis work did not cover this topic. We can think of many other issues that would raise when collaborators are not co-located. Interesting research questions might include how to best recreate the remote collaborator’s point of view on the model (a 3D minimap à la Greenberg & Gutwin?), and how to best offer explicit referencing support over a 3D surface.
Stephen Vickers, of De Montfort University, UK, is working on this fascinating research project to allow eye-tracking control of real-time 3D games. There are lots of reasons why this kind of research is relevant nowadays. Personally, I like two: first, these solutions can give disabled people the opportunity to equally participate to 3D online communities than able-bodied people; second, this technology can further extend the possibilities of able-bodied people in conjunction with other input modalities.
While we begin to have an extended knowledge of eye-tracking interaction for 2D worlds, few attempts have been made on 3D interfaces. This because of the increasing complexity of interaction possibilities. In virtual worlds we need to perform a large suite of commends in order to move a a character or avatar, change the viewpoint of the scene, and to manipulate objects. Finally we need an extra set of commands to communicate with other players.
The software developed by Vickers and collaborators approaches the complexity by splitting all these commands into different input modalities in order to subset the range of possible commands. Glancing momentarily off-screen in a particular direction switches between these modalities (e.g., to a mode that rotates the avatar or viewpoint, etc.). Also, the software allows the user to define gaze gestures to enable specific commands that do not belong to a certain modality, like that of turn off the eye-gaze control, to avoid unintentional selections.
I am a researcher at Telefonica I+D, in the Multimedia Group. The opinions/ideas expressed in this blog are personal and do not necessarily correspond to those of the company I work for.
In 2008, I have completed a PhD at the Swiss Federal Institute of Technology in Lausanne, Switzerland (EPFL), where I worked for the CRAFT laboratory.
I am currently conducting research on location-based applications. Although my main interests lie on human learning, I tend to publish in conferences such as CHI, E-CSCW, DIS, etc.
Keywords: locative media, collaborative annotations of maps, remote gesturing, eye-tracking, collaborative learning and work, e-Government, human-computer interaction, (and many more...)
Contact: martigan [at] gmail (dot) com
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