środa, 20 listopada 2013

Datatypes in Time

Data we gather has some time reference in it. It might me a moment or period which the data describes, time when data was collected, validity period or time when data got published. There's a range of situations when temporal attributes are understood in different ways.

Events happening at different places and times, traffic data (Google),
changes in tube stations log-in's/out's (Oliver O'Brien), crowdsourced data (irevolution.net)

Spatiotemporal data representing various phenomena can be analysed in few ways, depending on it's spatial and temporal characteristics. If the location is fixed (when using fixed sensors or with statistical data assigned to administrative areas) it is simply a matter of comparing values in time but when records represent unique locations (crowdsourced data, events) this can get more tricky when you want to dig deeper into data than just viewing data in selected time sections.

GDP change forecast (BusinessInsider), Road works (TfL), moving trains (WatchDogs game)

GIS data comes in 3 geometry types - points, lines and areas which are described with any numer of attributes. Analysing this data in temporal dimension requires us to use some identity attribute allowing creation of continuity between records when one record is a previous/future state of another record, thus letting comparisons to be made. As mentioned, fixed location data is a straight-forward situation, same with data records having unique identity (like buses or trains). Working with unique location data, use of aggregation (in a grid) or snapping helps create continuity of temporal dimension in data.

Shopfront changes (red triangles), workforce transfers planning with geocoded locations,
crime aggregated in 25m grid, major links closure (black) effects on traffic

Working on my spatiotemporal analysis app I decided to follow principles outlined in previous post and delivered:
- 4 views showing four moments in time, within selected range
- 1 view showing data dynamics (change in analysed value between first and last moment)
- simple interface updating all map views with single click

Currently the app is running properly with all types of data but requires script manipulation to switch between data types and kind of analysis. Here it is with UK GDP data (go fullscreen to see annotations).

Features for future version:
- adding meaningful content to time view (global parameter? data lines for each spatial element?)
- allowing easy switches for loading different data types and applying different analysis
- exporting animations to KML and maintaining a linked component in Google Earth

wtorek, 8 października 2013

GIS Time

Two fronts of development are considered to be revolutionising GIS. They are:
  • Visual – where more impressive and detailed 3d views deliver realistic vision of environment
  • Big Data – where streams of data, rather than collections, are being processed
These two are set in technology scene, as visual requires high-performance graphic hardware and big data requires high-speed data access and fast network connectivity. Therefore, breakthroughs in those fields are achievable with further development of hardware, infrastructure and database optimisation. What about other fronts to advance? There are options to push Urban GIS forward in areas where established standards are taken for granted and they limit our imagination of what can we achieve with GIS.

Interfacing with Time

Temporal dimension of data is at least just as inherent as it’s spatial dimension. Popular saying states that over 80% of our data is spatial or related to space. What about time? Isn’t all data a reflection of situation/object/phenomena observed at some point in time? Everything has its timespan so attribution of time to a feature is simply its beginning and end times.

Information required for single urban operation easily excess limits of clearly communicating data presented with tables or charts, that is why GIS is widely applied for solving problems in urban environments. Maps are great for exploring information, though there is little use made of temporal dimension of data in GIS applications. The most popular method of visualising dynamics is animation. They show several “slices” of time on a map,  the user can control playback or play it in a loop. This is analogic to exploring 3d worlds with pre-rendered scenes, where you cannot explore interactively. Main disadvantage keeping animations from being useful in real-life situations is the lack of comparability between timeslices (user has to rewind the animation or wait until loop repeats). Second major disadvantage is making the time factor a dimensions of hidden patterns which existence is expressed only by rapid change of display.

(Development phases)

(Movement illusion)

(Hispanic population dynamics in USA by Pew Research Center)

Lack of comparability between timeslices and implied linear causation.
Do we need a technological breakthrough to fix these? Or can we get satisfactory results with available off-the-shelf solutions? Let’s try to address outlined issues this way.

Simplest, straight-forward solution making timeslices comparable is to display at least two timeslices next to each other. Popular example is exhibition of before and after situation.

(Italian unification by Amit Men)

This can be scaled to display more timeslices at selected intervals and accompanying temporal data.
Example of similar array is display of spatial statistics with GeoDa.

(GeoDa interface, Jonathan W Lowe)

(Geo)graphic manipulation of time

For number of purposes GIS is a useful tool in solving problems not related to geographic or spatial relations between features but their relations in other dimensions which can be represented by any kind of graph. Attributed values and location in hypothetical space can be queried with Spatial SQL to aid the process of agreeing strategic objectives.

Strategic goals matrix used for city centre development planning

If time was drawn in 2d space (like maps are in GIS) this would be a line with markers representing occurrence of different events. These markers would occupy linear space, and as any data could be processed and displayed as derived layer. This space is divided into moments at defined resolution (days, hours etc.). Users view is an extent into which features/events fall. The extent exhibits itself as a movable box with lines over timeline and as timeslices in map views.
There is a strong tie between attributed values and timeline view. Just like maps are thematically formatted, so is the timeline. This makes timeline and map views related more than using the timeline only for view control. Events in timeline may be a different representation of mapped data (changes in value and temporal peaks rather than value intensity) and they are the strings of change connecting timeslice maps.

Timeslices and time map interface

Proposed solution gives simultaneous view on spatial and temporal information, letting the user navigate through space and time. It employs functionality of Manifold GIS and extends it with applications scripting capabilities. Benefits of this solution are serving two purposes: making the time view display filled with meaningful data showing mechanics behind processes observed in space and laying out static timeslices for comprehensive analysis.

środa, 25 września 2013

Lost proxemics of transit

The fact that now more than a half of world's population lives in cities is so obvious and talked through so many times that tackling it once again may seem like a no-go especially if one tries to emphasize pressures that are put on the environment, resources, infrastructure... oh, no, I will not go this way.

source: rozsavage.com

As a counter to all these repetitive calls for action to rethink, rebuild, adapt and whatever else they find necessary, I will voice an opinion of a regular citizen. One who can't see that now there is more of us in cities than in rural areas. One that can't see if our environment can take some more or if it's at the brink of a disaster. One that, really, doesn't care much about smart grids or externalities. Not because he's an ignorant or his intelligence won't let him think much outside the box. Simply he has his own problems on his mind. From the moment he leaves his apartment he passes his neighbours rushing, just like him, to work. Then he gets into an elevator already filled with those who, probably, live upstairs. But you never know if they really live there, or just regularly visit so it's hard to tell who's your neighbour. Than he gets to the station, also already filled with other commuters patiently waiting for the train to come. Little to no eye contact makes it easy to distinguish those who do it as a daily routine from those unassimilated newcomers trying to catch a glimpse of someones attention, hoping to see a smile or have a friendly chat. Forget it, you won't get any of that here. Instead you can look at a poster, read the "news" in a free paper ("Stuff your mind Daily") or dive into the virtual with your mobile device (some stations even offer WiFi, so you get anti-social quicker and for longer). Okay, let's cut it here. So what really bothers our average commuter? Density!

 source: deladream.com

Man is a social being, it's easier for us to live in families, it's more productive to work in teams and we generally spent our time better when we can interact. So what's better thing to do when you're with other people on a train, at the station, in a park or anywhere else where there's more of us? Is it looking blindly into distance, getting unreal with our mobile phones (browsing, playing games) or constantly shying away from other peoples eyes?

source: jaefiction.wordpress.com

We are all forced into being close to each other when traveling, yet there's no incentive to get interactive with each other. It's not hard to imagine how much more plausible experience it would be if the norm was to look, speak and act rather than try to hide and get past this moment as fast as possible. Behavioural change is needed to better manage this dense atmosphere. A shift from inward to outward social experience can be achieved without big investment and it only requires a recognition of a problem. City is not just it's systems and their capacity, it's (for the most part) the people who use these systems and how they feel about that.
Let me be clear on that: not huge investment, not more efficient machinery, not even less pollution will make cities much better- it's change in our behaviour, the moment we realise that we DO live together and we become happy about that, not just tolerant.

Not to sound like a moaner I will share a couple of ideas that could make transit experience more social, or at least worthwhile.
  1. Multiplayer gaming. Imagine if armrests were equipped with simple electronic devices letting passengers engage each other with games (e.g. chess, scrabble, cards, pong).
  2. Poetry read out loud or, known from facebook, "tube facts" sharing interesting info about history of the tube... or just anything that might catch attention and motivate to share impressions.
  3. Playing melodies. There is no better way to affect people's mood than music. Wouldn't you smile if you've heard a positive melody?
  4. Campaigns. Promoting friendly attitudes among commuters could take a form of informing people about other people who made friends on the tube, went on a date with someone met on the train, made a business there ("That's a really nice watch, where can I get one like this? - I sell designer watches, are you really interested?") or made others just feel better.
It's that simple.

czwartek, 19 września 2013

Secret urban designers

Our cities are made of large chunks of built-up areas crisscrossed with networks of transport systems hidden down under the surface or superimposed on and over it. Every few or more blocks you get a park or other amenity where one can find peace and space for physical activity. It's widely recognised that zones (housing, services, production etc.) mixed with green areas are what constitutes the city, proper ratio of these zones and distances which separate them define it's quality. The network seems to be there only to keep it all together and let us freely move from one place to the other, the streets are sometimes even called "infrastructure" to emphasize their subordinate role in serving the functional zones.

source: game SimCity 2013

That is where opinions diverge depending on how we define our perspective on the role of a city. Do we see the city as a machine, creating final product (economic output) in the most efficient manner or are we looking at the city as it was a collective of people who's well being and happiness makes the city an interesting destination and source of freedom and innovation bringing real prosperity. Yes, I am biased towards the latter, and I will not try to sound like I wasn't.

source: esolution-inc.com

Masterplanners, urban designers and architects all realise their responsibility in creating livable places in-between buildings and attractive scenery for urban living. They might have realised that not long ago, but they did and many of them do their best to negotiate solutions beneficial for both their clients and the wider public which (thanks to media and fast information propagation via internet) can turn an artist-titled-engineer into almost a celebrity persona (who couldn't name a few?) or make his name forever forgotten (amen). What about those who are rarely called designers but impact citizen life's even to a greater extent? Does it mean that a civil or traffic engineer is just a technician who, like a plumber or electrician, can make it work or not (1/0 situation)? And all those people that make public transport schedules and decide on parking rules, aren't they also entitled to be recognised as urban designers? I dare to say they are. And here is just a couple of reasons why:
  1. Civil engineers leave everlasting mark on our cities with bridges, viaducts, canals that "channel" our behaviour decisively more than even greatest architectural landmarks and, if speaking of landmarks, there are no other better recognised elements of cities than those great endeavours undertaken to bring closer the dreams of generations that buit them and secure future prosperity
  2. Traffic engineers make up rules by which we move around cities. They tell us where we can turn, where do we stop and what is the right place to cross the street, unless we want to get a ticket. Their rules affect our city experience to even higher degree when our cities get more dynamic with transport authorities trying to move more and more people and cars through same streets we have known for decades. It's hard not to agree that our journey is not less important than the destination.
  3. Transit scheduler decides on the number of vehicles servicing given transit line (bus, tube, tram or other) and, as a matter of fact, he is the one responsible for the wait times and making transit supply meet demand. If you spent a good portion of your way to work in a bus or underground, remember that it's the scheduler who works for your journey to be as seamless as possible.
This only a handful of professions who's role in designing urban landscape and citizen experience is underestimated. I could name more of them but for now, I would like to give my salutation to those three!

czwartek, 27 grudnia 2012

Bike share stations location analysis

Synergy of all means of transport will work for a coherent and effective system of access. Addition of a bike sharing system can attract more bus riding in areas where citizens are left with little choice of public transport possibilities. Such system should also support businesses where access is somehow limited. Where traffic is high and public transportation is unable to provide sufficient service, bikes can be an alternative for faster and more convenient mobility.

Masterplan analysis and phasing

Masterplan rules, when simulated, reveal key information on economic impact of implemented urban design. Knowledge of capital accumulation periods and spatial distribution of potentials along with planned public investments can keep business and community developing over a foreseeable future.

czwartek, 12 lipca 2012

External costs of road works

Many transport network development projects running here are built within already urbanized areas where they disrupt 'normal' flow of traffic in various ways at different locations and times. Years of rapid change are documented with hundreds of road works notifications published at city website. This database along with network modelling tools allow more insight into which links are more affected by higher traffic flows, places where traffic has calmed and which area units commute distance increased most, due to occuring road closures.