context: giscience perspective - · pdf file- analysis of patterns of change over time ! ......
TRANSCRIPT
Time and mapsMenno-Jan Kraak
Time and maps!
• Why interested in time?
• What is time and
• How is time perceived?
• How is time represented?
Why interested in time?
GIScience perspective:!
• Better understanding of human influence on the environment at all scales (local and global change)- analysis of changes over time - analysis of patterns of change over time !
• Development of methods / techniques / tools to be able to support problem solving- geospatial data handling- visualization
Context: GIScience perspective:
• For many (global) challenges reference to location - and time - is the glue that connects disparate, often incomplete data sources of continually changing information about time-critical, evolving real world situations
source: new york times
Earthquake & Tsunami Chili 27 Feb 2010 source: New York Times
What is time?
What is time?
• Everyone knows what it is, and few can define it
• what, then, is time? -
• if no one asks me, i know -
• if i wish to explain it to one that asketh, i know not
[st. augustine 400]
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• Time is about change
128 entries found in The New Oxford Dictionary of English
• time noun
• [mass noun] the indefinite continued progress of existence and events in the past, present, and future regarded as a whole
• a point of time as measured in hours and minutes past midnight or noon
• [mass noun] time as allotted, available, or used
• an instance of something happening or being done; an occasion
• ......
Past, present, future
• How, then, can these two kinds of time, the past and the future be, when the past no longer is and the future as yet does not be?
[Saint Augustine, 400]
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• Time as static (the now) versus time as dynamic (as flow)[Scientific American - A matter of Time, 2006]
Schools of thought
• absolute timeInfluenced by Newton they see time and space as a kind of container in which objects exist and move, guided by the laws of physics. Space and time function as a kind of reference frame. In other words, time is independent of any physical object, but it describes the ‘location’ of objects and events during their existence
• relative time Influenced by Aristotle, who said that time is measure of change, which in turn implies that time does not exist when there is no change. Leibniz and Kant were followers of this viewpoint. Space and time describe relations among objects
Perception of time
45 minutes
9 0 m i n u t e s
(this lecture)
Perception and structure of time
• Time has an inherent semantic structure, which is one source of increased complexity.
• By convention, time has a hierarchical system of granularities
- seconds, minutes, hours, days, weeks... (but different calender systems)
• Time contains natural cycles and re-occurrences.
- regular and relatively predictable: seasons,
- less regular: social cycles like holidays or school breaks or economic cycles, hurricane season
Sense of time
!• Timetables and rhythms
inter-relation between time and space such as seasons, tides, body, (island-boat)
• Social discipline monastery, factory, office, home
• Instruments and devicessun dial, vcr, satellite broadcast
• Texts
(from May, J. and N. Thrift, 2001. Timespace : geographies of temporality. Routledge, London)
Social time
• Time talks with an accent
- every culture has its own unique set of temporal finger prints
- to know a people is to know the time values they live by
Levine, R. (1997). A geography of time the temporal misadventures of a social psychologist, or how every culture keeps time just a little bit differently. Basic Books, New York
Time
• Time is about change > event
Water Resources, Vol. 32, No. 2, 2005, pp. 200–203. Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 223–226. Original Russian Text Copyright © 2005 by Semenchenko, Moroz.
Atlas to Alison's History of Europe, 1850; Plaste 78 - Passage of the Beresina, 26, 27 & 28 November 1812.
2011 sabbatical trip Berezina River, Belarus
!track process
!battle
Events Change
Temporal dimension
• Temporal primitives
- Time point is an instant in time
- Time interval is a temporal primitive with an extent
• The choice of appropriate primitives must depend on the properties of the data and the problem at hand.
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• Temporal structures exist
- Ordered time: linear and cyclic time
- Branching time
- Multiple perspectives.
Temporal scale
Calendars Types of time I
Structure of the temporal dimension (multiple perspectives)
• Time with multiple perspectives allows more than one point of view at observed facts (people’s observations about hazard events)
A > B > C> DDD > A > C > B
Types of time II
Different types of times
tekst
[Frank, A. U., 1998]
total order partial order branching multiple perspective
linear ordinal single experience
multiple experience
brancing time time with multiple prespectives
continious continious time
cyclic ordinal cyclic time
continious
Types of time?
• Valid time
• Transaction time
• World time
• Database time
• Observation time
• Display time
• Historical time
• Excavation time
• Mechanical time
• Biological time
• Body time
• Social time
• Life time
• Sense of time
• Web time
• .......
Different types of time Different types of time
Observe / measure time / change
• Change can happen suddenly or gradually
• Change of some sort is always happening
• Change can be observed after the fact
• Change can go unrecorded
Spatio-temporal data and questions
Temporal questions
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• When was the last forest fire in the neighborhood?
• Which areas were affected by mudflows in the week after the storm?
• In which neighbourhoods did the unemployment rise after closing the factories?
Temporal questions
Issues of representation!
• State (static)
What was / is / will be the spatial distribution of a given phenomena at a given time?
• Change (dynamic)
Which elements changed / are changing / will change during a given time span?
spatio-temporal data
Working environment for visual exploration
Time space
Location space Attribute space
M A P D I A G R A M
T I M E G R A P H
Working environment for visual exploration
Evaluation: time graph in its environment
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When and where?
When and what?
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When?
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What to do?
D A T A
- Linear and cyclic
- Instant and interval
- Absolute and relative
- Continuous and discrete
- .....
U S E R T A S K
• When
• How long
• How often
• What order
• .....
V I S U A L I Z A T I O N
• Time line
• Time wheel
• Diagrams
• Maps
• .....
How is time represented?
How to map events
Map AppearanceInformation retrieval
graphical variables
memory deduction
spatial deduction
memory deduction
graphical variables
graphical variables
graphical variables
plane
plane
plane
time location attributesingle map
animation
small multiple (series of maps)
I
III
II
Single map Series of maps
Animation Historical geography
§ study through time of human relationships to physical environment and human organization of an area
§ time as a line / dating an event: moments
when did the conference take place?
§ duration: how long and event takes place
how long does it take for an event to occur in how much space? (sample: epidemic)
Historical situations Reconstructing history
Mapping uncertainty Compiling change
Cultural geography
§ impact of human culture on natural environment and how space is organized
§ internal processes: perceiving time
§ external processes: structured time
time table
time zone
Experiencing time
45 minutes 9 0 m i n u t e s
Time zonesWhere is my package? dhl from schiphol to….
morning, afternoon, evening
Time geography
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§ time as measurement of human activity
what did people do and how long did it take?
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§ time as a measure of distance
isochrones (lines of equal temporal distance)
chrono-geographic representation (space time cube)
Time travel
Travelling from enschede (cartogram) France and the tgv in 2015
Distance time relief in france
[L’Hostis]
Space-time-cube
Crime over time
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http://projects.nytimes.com/crime/homicides/map?hp
Map background
What, where and when Troia – valley of scamander coastline changes trough time
Spatial Analysis & Cartography Laboratory (ErGAX) FOUNDATION OF THE HELLENIC WORLD
Troia – prehistoric period
Troia
Troia – homeric period
Spatial Analysis & Cartography Laboratory (ErGAX) FOUNDATION OF THE HELLENIC WORLD
Troia Troia
Troia – roman period
Spatial Analysis & Cartography Laboratory (ErGAX) FOUNDATION OF THE HELLENIC WORLD
Troia
Spatial Analysis & Cartography Laboratory (ErGAX) FOUNDATION OF THE HELLENIC WORLD
Troia – present day situation
Troia
Time?
• There is no time
• Time is relative
• Time is absolute
• Its all in your head
• What is time?
[Irena Vasiliev, (Cartographica vol 34 no 2 1997]