#citysdk

[omriziv]

איך מנהלים עיר חכמה בזמן אמת?

כיצד מנהלים מטרופולין עם מיליוני תושבים ?  במהלך  חודש מאי התקיים אמסטרדם כנס בנושא ערים חכמות בו הציגה קבוצת היי-טקיסטים צעירים בשם CitySDK את התשובה -  לוח המכוונים העירוני (City Dashboard) המציג נתונים בזמן אמת אודות מצב הכבישים, התחבורה הציבורית, זיהום האויר והבטיחות ברחבי אמסטרדם. עוד טרם הכנס,  עיריית אמסטרדם פתחה לשימוש הציבור מאגרי נתונים רבים בפורמטים שונים ובאתרים שונים. כחלק מפרויקט ה-

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[trafficplus]

Traffic+ Ayrıntıları ve Bitiş

Sunumların teslim edilmesine bir saat kala artık Hackathonu ve uygulamamızın ayrıntılarını toparlamamız gerekiyor. Buradaki herkes neredeyse hazır, artık kod sayfaları değil sunum sayfaları görünüyor ekranlarda. Yavaş yavaş bu güzel 2 günlük etkinliği sonuna geliyoruz.

İlk günkü tanıtımdan itibaren TAGES çalışanları olsun, Turkcell olsun, İBB görevlileri olsun herkes o kadar yardımcı ve güleryüzlüydü ki organizasyonda yaşanan(taşınıp durmak gibi) sıkıntılar bile rahatlıkla göz ardı edilebildi. İlk gecenin sonunda Turkcell sayesinde User Experience Lab'de Turkcell battaniyeleriyle rahat bir gece geçirdik. Ne çayımız eksikti, ne kahvemiz ne de yiyeceklerimiz. Bütün enerjimizi sadece geleceğin akıllı şehir İstanbul için uygulama geliştirmeye adadık.

Yavaş yavaş başlayan hackathon gün içerisinde hız kazandı, gece büyük enerji düşüşleri yaşandı ancak son güne gelindiğinde teslim saatinin yaklaştığı hızla aynı ivmede bir hızlanma gördük herkeste. Şu an da sunumlara 1 saatimiz var ve hissettiğimiz en baskın şey heyecan!

Traffic+'ın bu 31 saatte ne için uğraştığından bahsetmek istiyorum biraz da. Traffic+ olarak amacımız crowdsource yöntemiyle, mobil teknolojileri birleştirerek sürücülere en gerçek ve tutarlı bilgiyi sunarak trafikte rahatlarma sağlamaktı. Bunun için tasarladığımız uygulamanın yaptığı ise lokasyonu algılanan kullanıcının geçtiği yerde karşılaştığı trafik sorunlarıyla ilgili ses kayıtları bırakması, daha sonra da o bölgeye ulaşmasına 5 dk kalmış kullanıcıya bırakılan kayıtların en yeniden eskiye doğru dinletilmesi. Örneğin Maslak'tan Etiler'e giderken bir kaza fark ettiniz ve kazayı anlatan ses kaydınızı kaydettiniz. Daha sonra ben Maslak'tan yol çıktım ve temden Etiler'e doğru yol alıyorum. Benim ses kaydı bırakılan çevreye yaklaştığımı anlayan uygulama bana sizi bıraktığınız kaydı dinletiyor otomatik olarak. Yüksek mobil datalar gerekir! dediğinizi duyar gibiyiz. Ancak endişeye gerek yok. CitySDK şimdilik trafik datasını bize veremiyor bu yüzden Yandex'ten aldımız harita bilgisi ve kullanıcıların hız değişimlerinden hesapladığımız trafik durumu bilgisini CİtySDK ile paylaşıyoruz. İleride paylaşıldığında harita offline olarak kullanılabilir olacağından çok daha küçük datalardan bahsediyor olacağız. Ses kayıtlarını ise sıkıştırarak yolladığımızda 15 saniyelik bir kayıt 100 kb civarında tutuyor.

Bu uygulamanın uygulanabilirliği için daha önceki yazılarımızda bahsettiğimiz anket çalışmaları da yine hackathonist kapsamında gerçekleşti ve sizinle paylaştığımız sonuçları da sunumumuza ekledik. 

Gelir modeli içinse lokasyon bazlı pazarlama en güzel seçenek bizim için. Diyelim ki hesapladığımız hızınıza göre 5 dk içerisinde İstinye Park'a ulaşabilecek mesafedesiniz. O yarıçapa girdiğiniz an İstinye Park'ın ya da içerisindeki mağazaların reklamlarını bırakılmış ses kaydı gibi dinleyeceksiniz. Ancak bu 15 dk da bir sadece 15 saniyenizi alacak ve sizi bunaltmayacak. Uygulamanın geleceğinde ise uygulamanın hava durumu bilgisiyle beslenmesi ve buzlanma olacak yoldan geçtiğinizi anladığında size bu uyarıyı yapıp peşinde de bir lastik firmasının reklamını yayınlaması gibi spesifik reklam türleri planlamaktayız.

Ayrıca ileri ki sürümlerde gamification yöntemleri uygulamak için bıraktığı ses kayıtlarına göre kullanıcıya bagdes vermek, tıkanmış yollar için yol önerilerinde bulunmak ve en önemlisi trafiği azaltmak adına aynı zaman aralıklarında aynı bölgelere gitmeye çalışan insanları logladığımız bilgilerden saptayıp car pooling'e yönlendirmek hedeflerimiz arasında. 

Umarım traffic+ kazananlardan biri olacak ve geliştirmelerle gerçekten bir girişime dönüşerek, girişimci ruha sahip 3 insanı hedeflerine ulaştıracak.

Uygulamaya ait screenshotlar aşağıda yer almakta.

[trafficplus]

24. Saat'i Bitirdik!

Hackathonist'in 24 saatini geride bıraktık. İlk gün akşam yemeğinde Turkcell'in user experinece labaratuarına taşındık. Güzel bir akşam yemeğinden sonra tekrar mekanikleşmiş klavye sesleri duyulmaya başlasa da gece yarısından sonra yorgulunluk belirtileri görümeye başlandı. Hepimizin imdadına Turkcell'in battaniyeleri ve armutlar yetişti. Sabah kadar çalışan da oldu dayanamayıp uykuya yenik düşen de.

24. saate ise yine yarışmanın başladığı alanda, yine bizim için hazırlanmış güzel bir kahvaltıyla giriyoruz. Ödüller gelmiş ve masada yerini almış bile! Turkcell sanki görüp motive etmek istiyor bizleri. Herkes dinlenmiş kaldığı yerden devam ediyor hızla. Uygulamasını bitirenler olduğunu duyuyoruz kulislerde ancak emin olarak söyleyebileceğimiz tek şey Traffic+'ın yaklaşık %90 oranında bittiği. Sunumlara yaklaşık 8 saatlik bir zaman kaldı ve bu alandaki herkes için heyecan dorukta. Traffic+ olarak şimdiden herkese başarılar diliyoruz. 

[trafficplus]

Pazar Araştırmalarımız

Herkese merhabalar,

Traffic+ uygulaması takımın developerları sayesinde gelişirken diğer taraftanda fikrin ilerideki gelişimi açısından tutup tutmayacağı, kullanılacak bir kitlesinin olup olmadığı gibi sorular aklımızda kalmasın istedik ve bir anket düzenledik. 8 soruluk bu kısacık anketimizi isterseniz (gelişime devam edileceği için) şu adresten http://sdrv.ms/17DD26U hala doldurabilir ve değerli fikirlerinizle araştırmayı besleyebilirsiniz. Ancak malumunuz yarın bir sunum olduğu için bazı sonuçlara ulaşmamız gerekiyordu. Bunun için anketimizi hem internet aracılığıyla açtık hem de kampüsün içinde ve yarışma alanında birebir doldurduk. Sunum içerisinde her sonuca yer veremeyeceğimiz için de sonuçların grafiğe dökülmüş halini sizlerle buradan paylaşmak istedik. 

Sorular şu şekildeydi; 1) Yaşınız?

2) Cinsiyetiniz?

3) En son mezun olduğunuz okul?

4) Araç kullanıyor musunuz?

5) Navigasyon kullanıyor musunuz?

6) Hangi navigasyon uygulamasını kullanıyorsunuz?

7) Navigasyonu nereden kullanıyorsunuz?

8) Uygulamalara login olurken telefon numarası mı kullanmak istersiniz facebook mu?

Yanıtlar da aşağıda geliyor.

[trazeapp]

Points of Interest informations: CitySDK vs Foursquare vs Mingle

Today we are going to answer the question: "What's around me?"

To do so, we will query three different services that provide "Point of Interests" information:

CitySDK API

Foursquare Venues API

Mingle.io API

The queries we will run:

Foursquare query: https://api.foursquare.com/v2/venues/search?ll=52.373056,4.892222&radius=100

Mingle query:  [ {a.name, a.lat, a.lon, a.amenity, a.tourism, a.opening_hours, a.fee, a.type, a.information, a.historic} | a <~ osmpois, dist(a.lat, a.lon, 52.373056, 4.892222) < 0.100]

CitySDK Query:  http://api.citysdk.waag.org/nodes?lat=52.373056&lon=4.892222&radius=100&layer=osm&per_page=100

CitySDK Finds a lot of info. Problem: some data has no name.

EXAMPLE: let's have a look at the data associated with "The Royal Palace" (Koninklijk Paleis)

Foursquare:

"id": "4a270706f964a520bc8c1fe3", "name": "Koninklijk Paleis Amsterdam", "contact": { "phone": "0206204060", "formattedPhone": "020 620 4060" }, "location": { "address": "Nieuwezijds Voorburgwal 147", "crossStreet": "Dam", "lat": 52.37313639562877, "lng": 4.891362190246582, "distance": 59, "postalCode": "1012 RJ", "city": "Amsterdam", "state": "Noord-Holland", "country": "The Netherlands", "cc": "NL" }, "categories": [ { "id": "4bf58dd8d48988d12d941735", "name": "Monument / Landmark", "pluralName": "Monuments / Landmarks", "shortName": "Landmark", "icon": "https://foursquare.com/img/categories/building/default.png", "parents": [ "Professional & Other Places", "Government Building" ], "primary": true } ], "verified": false, "stats": { "checkinsCount": 2351, "usersCount": 1833, "tipCount": 15 }, "url": "http://www.paleisamsterdam.nl", "likes": { "count": 0, "groups": [] }, "beenHere": { "count": 0 } },

Mingle.io:

{ "a.name": "Koninklijk Paleis", "a.lat": 52.37314, "a.lon": 4.89135, "a.amenity": "", "a.tourism": "attraction", "a.opening_hours": "", "a.fee": "", "a.type": "TOURIST_CASTLE2", "a.information": "", "a.historic": "castle" },

CitySDK:

{ "cdk_id": "r1604009", "name": "", "node_type": "node", "layers": { "osm": { "data": { "type": "multipolygon", "tourism": "attraction", "name": { "es": "Palacio Real" } } } }, "layer": "osm" },

Why is in CitySDK only the Spanish name available? 

It's awesome that we get a MultiPolygon, but there's little data associated to it!

[trazeapp]

The Hunt for POIs (Points of Interests)

POIs are the key. 

But how to get that data?

Lets find out:

What I need for app:

locations and borders (where available)

know in which administrative region a place belongs

draw administrative regions borders

distance from the city center

What I look for in this document:

A catalog of Points of Interest (POIs)

better if “open data”

Caution! Open Data does not mean that I am not going to pay for the service! (see Mingle.io as an example)

General resources:

http://gis.stackexchange.com/

https://help.openstreetmap.org/questions/15/getting-point-of-interest-data-from-openstreetmap

http://wiki.openstreetmap.org/wiki/List_of_OSM_based_Services (not useful)

The POI database is 28GB and downloadable. http://stackoverflow.com/questions/1875255/open-source-poi-database

Getting POIs: http://www.quora.com/What-are-the-pros-and-cons-of-each-Places-API

Discussion about POI services: http://gis.stackexchange.com/questions/10299/poi-datasets-for-north-america

Aggregators from various (Open) Data sources

SimpleGEO / Factual

SimpleGEO is no more, it has been bought by Urban Airship (http://blog.programmableweb.com/2012/01/12/simplegeo-apis-closed-but-places-data-is-open/ )

Now the data is in Factual: www.factual.com (unclear how much it costs...)

They have a iOS SDK + iOS Demo on GitHub, however in the demo only the US POIs database is used.

Mingle

https://mingle.io/api

A service to query POIs from various datasets.

To query OSM:

[ {a.name, a.lat, a.lon, a.amenity, a.cuisine} | a <~ osmpois, a.type =~ "FOOD_" ]

Playing with Mingle.io API

[ {a.name, a.lat, a.lon, a.amenity, a.tourism, a.opening_hours, a.fee} | a <~ osmpois, a.type =~ "TOURIST_", a.tourism =="museum" ]

→ gets us all museums in the dataset!

dist(e.lat, e.lon, 51.5019, -0.1274) < 0.300

[ {a.name, a.lat, a.lon, a.amenity, a.tourism, a.opening_hours, a.fee, a.type, a.information, a.historic} | a <~ osmpois, a.type =~ "TOURIST_", a.tourism =="museum",  dist(a.lat, a.lon, 51.5019, -0.1274) < 0.300]

--> 1 result (chuirchill war museum)

[ {a.name, a.lat, a.lon, a.amenity, a.tourism, a.opening_hours, a.fee, a.leisure, a.natural, a.type, a.information, a.historic} | a <~ osmpois, a.leisure=="park",  dist(a.lat, a.lon, 51.5019, -0.1274) < 0.300]

--> 1 result (parliament square)

[ {a.name, a.lat, a.lon, a.amenity, a.tourism, a.opening_hours, a.fee, a.leisure, a.natural, a.type, a.information, a.historic} | a <~ osmpois, a.type =~ "POI", dist(a.lat, a.lon, 51.5019, -0.1274) < 1.300]

--> Generic POIs in London

To ask more than 10 results, need to use the API

A correct JSON call is as follows: (Note the \ ESCAPE char)

{

   "expr": "[ {a.name, a.lat, a.lon, a.amenity, a.tourism, a.opening_hours, a.fee, a.leisure, a.natural, a.type, a.information, a.historic} | a <~ osmpois, a.type =~ \"POI\", dist(a.lat, a.lon, 51.5019, -0.1274) < 1.300]",

   "limit": 10

}

CitySDK

http://dev.citysdk.waag.org/

"The CitySDK Linked Open Data Distribution API is a linked data distribution platform. Developed by Waag Society, the distribution API is a component of the CitySDK toolkit. This toolkit supports the development of open and interoperable interfaces for open data and city services in eight European cities (Amsterdam, Helsinki, Manchester, Lisbon, Istanbul, Lamia, Rome and Barcelona). The CitySDK Linked Open Data Distribution API enables the distribution and linking of open data sets and city services. " CitySDK is a very powerful API as it allows to do something different from the rest:

queries based on the administrative region (e.g. query what are the railway stations within a certain city's borders)

working with borders of objects (you can get the border of parks, for example. Very cool!)

However data from OSM is currently not up-to-date. Moreover, some points of interest are duplicated among many layers. While the latter is an issue that requires a different approach to be solved, the real limitating factor here is the inaccuracy of Open Streetmap Data, not the power of the API itself.

Open Data Maps

GeoNames

http://www.geonames.org/

The GeoNames geographical database covers all countries and contains over eight million placenames that are available for download free of charge.

They offer JSON services, for free with daily limit based on “credits” (30.000 credits per day). Credits are tracked by login name (registered users, for free). Address is: http://www.geonames.org/export/JSON-webservices.html

Features:

Reverse geocoding

Administrative regions

get POIs nearby to a certain lat,lon (4 credits).

examples of calls to API:

view-source:api.geonames.org/search?country=NL&name=Amsterdam&username=[YOURUSERNAME_HERE]

view-source:api.geonames.org/search?country=NL&name=Amsterdam&adminCode1=NH&username=[YOURUSERNAME_HERE]

To search for a city called amsterdam in adminCode1=07 (Noord Holland):

view-source:http://api.geonames.org/search?country=NL&name=Amsterdam&adminCode1=07&featureCode=PPLC&username=maggix

Search for a city called Rotterdam:

view-source:http://api.geonames.org/search?country=NL&name=Rotterdam&featureClass=P&featureCode=PPL&username=[YOURUSERNAME_HERE]

Problem with this search comes in US:

view-source:http://api.geonames.org/search?country=US&name=Sacramento&featureClass=P&featureCode=PPL&username=[YOURUSERNAME_HERE]

OpenStreetmap

www.openstreetmap.com

Using OpenStreetMap: http://wiki.openstreetmap.org/wiki/Using_OpenStreetMap

Map Features:

These are the “things” we want to take out from OSM:

http://wiki.openstreetmap.org/wiki/Map_Features

Nominatim:

“Nominatim (from the Latin, by name) is a tool to search OSM data by name and address and to generate synthetic addresses of OSM points (reverse geocoding). It can be found at http://nominatim.openstreetmap.org . Nominatim is also used as one of the sources for the Search box on the OpenStreetMap home page and powers the search on the MapQuest Open Initiative websites.”

Web service: http://nominatim.openstreetmap.org/

Query and obtain JSON: http://nominatim.openstreetmap.org/search.php?q=Vondelpark%2C+Amsterdam&format=json

How to use it: http://wiki.openstreetmap.org/wiki/Nominatim

However, I do not need Nominatim. I need a list of POIs.

XAPI:

http://wiki.openstreetmap.org/wiki/Xapi

There are various services implementing this API, they are hosted by various companies. See InformationFreeway, Nogago or (quoted below) OpenMapQuest.

OVERPASS API:

Overpass API seems more powerful than XAPI. However unclear how to query it:

http://wiki.openstreetmap.org/wiki/Overpass_API

MapQuest

"MapQuest is an online mapping company based in the United States and is wholly-owned by AOL." (Wikipedia)

www.mapquest.com

Mapquest offers an iOS SDK to use OpenStreetmap tiles into app, but uses licensed API: http://developer.mapquest.com/web/products/featured/apple-ios-maps-api (at this page for download link)

Refer to README.TXT for setup

For paid services:

## Using MapQuest Commercial Services (MapQuest map tiles and Geocoding)

To use MapQuest commercial services, you will need to add the following property to your application's info.plist file:

   MapQuest.Map.Key

Set the value of this property to your MapQuest key.

MapQuest Open

MapQuest Open Data maps: http://open.mapquest.com

Editing Open Data maps with Potlatch2 from MapQuest: http://developer.mapquest.com/web/products/open/tools/edit

MapQuest Open Data maps products: http://developer.mapquest.com/web/products/open

It’s possible to query OpenMapQuest and get back JSON, by using this GET request in Postman (add-on for Chrome): http://open.mapquest.com/_svc/searchio?action=mapSearch&query=Parks&shapepoints=-121.22448753036838,49.90014915101582,-77.05944846963166,27.340340242846267&mapSearchArea=(39.54454183982155,-99.16394065624912,13867001,1005,667,1.0,1.0)

(this request will return Parks in the U.S.)

XAPI:

What is it: http://developer.mapquest.com/web/products/open/xapi

User guide: http://open.mapquestapi.com/xapi/ (old! Not updated!)

Sample GET request: http://open.mapquestapi.com/xapi/api/0.6/node[amenity=pub][bbox=-77.041579,38.885851,-77.007247,38.900881]

---> Response is an XML . Tested with Postman

Beginner’s guide to OSM:  http://developer.mapquest.com/web/products/open/tools/guide

The product I need is MapQuest Discover: http://discover.mapquest.com/  ← are there API for it?

MapQuest Licensed API:

Search: http://developer.mapquest.com/web/products/dev-services/search-ws (5000 free per day, otherwise Enterprise License needed, $ 2500 per year)

MapBox

“We started MapBox to make it easy for anyone to design and publish a beautiful custom map.

Our platform gives developers the power to make maps that embody their product and brand. MapBox helps you find bars on foursquare, search for hotels on Hipmunk, and organize notes in Evernote. With our global, autoscaling infrastructure and cross-device compatibility, integrating our maps into your apps is easy even if you have millions of users.”

MapBox provides a SDK to embed in a iOS app their maps. The strength of MapBox is the possibility of using custom map tiles, and that is able to get Polylines out of GeoJSON files, without the need to parse it as I do in the iOS MapKit SDK.

Starting page for developers: http://www.mapbox.com/developers/

MapBox does not provide API to get POIs, so although the MapBox SDK looks quite powerful (allows easy conversion from GeoJSON data to Polylines), it is useless for getting POIs.

Mapbox helped developing the editor for OSM.

http://www.openstreetmap.org/edit?editor=id

Foursquare

Foursquare has the concept of Venues: https://developer.foursquare.com/overview/venues

“Just need a database of places? The Venues Platform allows developers to search for places and access a wealth of information about them, including addresses, popularity, tips, and photos. It's available free and without any user authentication, as long as applications include adequate attribution.”

Facebook Places

https://developers.facebook.com/docs/reference/fql/place

Foursquare requires the user to be logged in to Facebook to access the places.

(Consider using Facebook as a platform also for Leaderboards, user login, etc. This would be the basis to build a Facebook Game)

Bing Maps

http://dev.virtualearth.net --> http://msdn.microsoft.com/en-us/library/dd877180.aspx

To get POIs, with Bing Maps we have to use “Spatial Data”.

http://msdn.microsoft.com/en-us/library/ff701734.aspx

“The Bing Spatial Data Services are REST-based services that offer three key functionalities: batch geocoding, point of interest (POI) data, and the ability to store and expose your spatial data. These services are ideal for those who need a place to store their spatial data, or who need point of interest data in their application. “

Query example for POIs in EU:

http://spatial.virtualearth.net/REST/v1/data/c2ae584bbccc4916a0acf75d1e6947b4/NavteqEU/NavteqPOIs?spatialFilter=nearby(50.1120796203613,8.68340969085693,100)&$select=EntityID,Latitude,Longitude,DisplayName,__Distance,LanguageCode&$top=3&key=anyBingMapsKey

Google Places

https://developers.google.com/places/documentation/

For searching for POIs nearby, the search would be:

https://maps.googleapis.com/maps/api/place/nearbysearch/output?parameters

(see: https://developers.google.com/places/documentation/search#PlaceSearchRequests )

Is there an iOS Library?

No

Google API Client Library for Objective-C has no support for Places (or Maps)

Google Maps SDK for iOS is only for showing map

Look at this tutorial: http://www.raywenderlich.com/13160/using-the-google-places-api-with-mapkit

Usage Limits

The Google Places API has the following query limits:

Users with an API key are allowed 1 000 requests per 24 hour period.

Users who have verified their identity through the APIs console are allowed 100 000 requests per 24 hour period. A credit card is required for verification, by enabling billing in the console. We ask for your credit card purely to validate your identity. Your card will not be charged for use of the Places API.

While the lower limit is sufficient for development and testing, we recommend enabling the higher limit before launching your application. It is possible to request additional quota.

Note that some services may have a multiplier. For example, Text Search is subject to a 10 times multiplier, causing each Text Search request to count as 10 requests against your quota.

Yelp!

API: http://www.yelp.com/developers/documentation/v2/overview

Samples: https://github.com/Yelp/yelp-api

(Note: the samples only build a Yelp API client library and not a demo project)

[erikromijn]

CitySDK @ WaagOpenSpace

CitySDK offers an API which makes it easy to build digital services that use open data. At CitySDK @ WaagOpenSpace, developers of the API talk about the API and what they plan to do with it. This is my summary of the evening.

Job Spierings: CitySDK introduction

Job Spierings started the introduction by reiterating that open data for the CitySDK is important for transparency; releasing social and commercial value; and participation and engagement. However, many open data users run into the familiar issues: different formats, sometimes proprietary; differing refresh rates in data; potential privacy issues, like cellphone numbers for workers in road works data; and legal issues caused by datasets having many different owners with different interests.

CitySDK aims to solve these issues for developers. In Tim Berners-Lee stars, they aim to be between four and five stars. CitySDK does not just take data from governments, but also uses crowd sourced data, to create what they call: crowd enhanced data.

THe project is set up to become a one-stop-shop for developers, with pan-european access. Current cities are Lisbon, Barcelona, Manchester, Amsterdam, Rome, Helsinki, Lamia and Istanbul. The whole project is also open source. Not all datasets are available in all cities. Maps, based on OpenStreetMap, are available in all cities, public transport is available in most.

They've built a few demo applications, like 'now', which shows departure times at nearby public transport stops. This has been done before, but unique about this app is that it works in cities in various European countries, while using only a single API. They are working on the Open City Dashboard, which can be used by municipalities to communicate about the state of the city to citizens.

Bert Spaan: Meet the City SDK API

Bert Spaan takes us into the CitySDK platform. He's one of the backend developers of the CitySDK mobility API, and uses the example of Amsterdam Central Station. There are many datasets available today, like OpenStreetMap, the NS realtime departure times, and even Foursquare. But they are all very difficult to link. By using common identifiers, as Tim Berners-Lee intended, data can be linked.

CitySDK takes these identifiers from OpenStreetMap, using it as a geographic base layer. They then map other datasets, like GVB departure times, to these OSM nodes. OSM works well for this, because it's very complete. Bert recently went to Manchester, and the same principles apply there.

Linking datasets is incredibly hard. There are many different spellings and names. Mapping on geographical proximity is also not sufficient. Some of the processing in CitySDK is automatic, but they still do some handwork. An example for this is the DIVV realtime travel times dataset. This data contains coordinates of the roads for which the speed is measured, but those coordinates do not exactly overlap with OpenStreetMap roads. They've developed algorithms to map these quite well.

Bert gives us a demo of the map viewer which is a really nice way to explore CitySDK data. I'm quite impressed: a nice example is linking the OpenStreetMap object of Artis to the ArtsHolland API, so that you can go directly and reliably from the OSM object to the next 'Knuffelen met kleine dieren'.

Laurens Schuurkamp: CitySDK globe

Laurens is a frontend developer at the Waag society. A year ago, he built a tool that aggregated all 32 open datasets available for Amsterdam at that time. But the biggest problem was that they could not be combined.

The built a new wonderful visualisation now, the CitySDK globe (requires WebGL). Again, the most impressive part is that most data they can show for Amsterdam, is available for Manchester and other cities as well.

Roel Obdam

Roel is a student that works on combining external datasets with the CitySDK. For example, one could take all tourism nodes from OSM, and then run another query against a different API that adds data about museums - from an API that is not included in CitySDK itself.

They use DBPedia for matching. Unfortunately, it's not entirely reliable at this time. After querying both datasets, a user can define which attributes should be linked to each other. It's not specific to CitySDK: it will be able to match any two datasets to each other.

Jonathan Carter: Towards a multimodal API

Jonathan from Glimworm IT talks about "Towards a multimodal API", a report for the Department of Infrastructure, Traffic and Transportation of the city of Amsterdam, which Glimworm wrote together with myself and Braxwell.

The purpose of the project was to see how possible it currently is to make the perfect multimodal API, which areas need improvement, and what DIVV can do. We focused on route planning and real time monitoring of planned routes. One of the results is a proof of concept which does multimodal planning with different data sources. For example, you could go from Woerden to the Rijksmuseum by car all the way, bike all the way, OV all the way, or bike to a station and then use OV, or take a car to any of the park and rides and then OV, and so on.

The biggest challenge is prediction. If the planner sends someone to a park and ride, because that's good for both the traveller and the city, and the park and ride is full, the traveller will be very disappointed, and might never consider this again. This problem extends to pretty much all data: realtime info focuses on the state right now, but there are no good predictions for the future. This is especially critical when a traveller has to switch between modes of transport.

Rein van Oost: Expected Time of Arrival

Rein presents "Expected Time of Arrival", their idea for an app on the CitySDK. They've been making open data apps since 2008. They were asked to come up with a practical application of the CitySDK data.

Their idea, "Estimated Time of Arrival", uses the CitySDK mobility data. The concept is to share your current position, direction and destination with others. The app estimates the time of arrival at the destination, so other people don't have to ask you when you will be home or whether you will be on time.