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Spatial Decision Support and GIS. NCGIA Core Curriculum Unit 127 - Spatial Decision Support Systems by Jacek Malczewski, Department of Geography, University of Western Ontario, Canada. Using GIS. GIS and computers can synthesize data and perform analysis and modeling - PowerPoint PPT Presentation
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Spatial Decision Support and GIS
NCGIA Core CurriculumUnit 127 - Spatial Decision Support Systems
by Jacek Malczewski, Department of Geography, University of Western Ontario, Canada
Using GIS
• GIS and computers can synthesize data and perform analysis and modeling
• But PEOPLE make decisions!
• How can GIS be used as part of the decision-making process?
• Decisions can be top down (managers) or bottom-up (public participation)
Spatial Decision Problems
The main characteristics of spatial decision problems include: – Many alternatives, – Consequences of the decision alternatives are spatially variable – Each alternative is evaluated on the basis of multiple criteria, – Some of the criteria are qualitative others quantitative– More then one decision maker (or interest group) involved in the
decision-making process– Decision makers have different preferences on evaluation
criteria and decision consequences– Decisions are often surrounded by uncertainty
– NIMBYism etc.
Tampa Bay RegionTampa Bay Region
Emergency ManagementDecision Support GIS
For the
Emergency ManagementDecision Support GIS
For the
EmergencyManagementEmergency
Management
• Domestic preparedness• Vulnerability Assesments• Mitigation planning• Training• Incident management• Recovery
• Domestic preparedness• Vulnerability Assesments• Mitigation planning• Training• Incident management• Recovery
Input Wind Radii
Identify Parcels
Notify Owners
Assess Damage
Plot Storm Track
RVAM
Notify NowExtreme Risk Property Owners
Assess FutureGrowth Scenarios
Future Growth Losses
Scenario 1
Scenario 2
Input Wind Radii
Identify Parcels
Notify Owners
Assess Damage
Assess FutureGrowth Scenarios
Plot Storm Track
RVAMAssess NowRisk Damage Assessment
Parcels Affected
$ Building Loss Estimate
Extreme
High
Moderate
5299
5343
7167
1,964,336,700
1,830,798,900
591,793,600
Extreme100% Loss
High75% Loss
Moderate50% Loss
Assessment Complete
12,382,300
7,564,900
Save Resultsand Exit?
Yes NoYes No
Historical Background
• Decision Support System (DSS) based on work by Herbert A. Simon in 1950s and 1960s (Simon 1960);
• DSS evolved during the 1970s and 80s • SDSS concept has evolved in parallel• IBM's Geodata Analysis and Display System 1970s
earliest large DSS • SDSS has been associated with the need to expand the
GIS capabilities for complex, ill-defined, spatial decision problems
• Major growth in research, development, and applications of SDSS in the last 10 years
• Many threads with different, but related names, such as collaborative SDSS, group SDSS, environmental DSS, spatial knowledge based and expert systems, PPGIS
The Decision-making Process
• Simon divides any decision-making process into the phases of decision-making – intelligence - is there a problem or an
opportunity for change? – design - what are the decision alternatives? – choice - which alternative is best?
Planning Stages
• Problems• Goals• Objectives• Alternatives• Evaluations• Choice• Implementation• Monitoring
Planning Methods
• SWOT• Bargaining• Brainstorming• DELPHI• Scenario writing• Consensus building• Public meeting support• Charrette• Consultants• Stakeholder involvement• Outreach
GIS and Decision Support
• GISystems have limited capabilities to support the design and choice phases of the decision-making process
• GIS provides a static modeling environment , reducing their scope as decision support tools
• Especially so in the context of problems involving collaborative decision-making
What is SDSS?
• SDSS is an interactive, computer-based system designed to support a user or group of users in achieving a higher effectiveness of decision making while solving a semi-structured spatial decision problem;
• The three terms (semi-structured spatial problems, effectiveness, and decision support) capture the essence of the SDSS concept
Components of SDSS
• Data Base Management System contains the functions to manage the geographic data base
• Model Base Management System contains the functions to manage the model base;
• Dialog Generation and Management System manages the interface between the user and the rest of the system.
DSS Tools• Procedural programming languages and code libraries (e.g.,
VB, AML, Avenue, TransCAD - Caliper Script macro language, MapInfo - MapBasic);
• Visual progamming language (e.g. STELLA, Cantata and Khoros);
• Inter-application communication software (e.g. dynamic data exchange (DDE), object linking (OLE), open database connectivity (ODBC));
• Simulation languages and software (e.g. SIMULINK, SIMULA); • Application programming interfaces (API) (e.g. the IBM's
geoManager API, Java Advanced Imaging API, TransCAD's API);
• Applets (e.g. GISApplet, Microsoft Visual J++), • Visual interfaces, graphics and color subroutines (e.g.
graphical user interfaces – GUI, OpenGL, SVG, etc.)
DSS Generator
• Package of related hardware and software which provides a set of capabilities to quickly and easily build a specific SDSS
• GISystems (e.g. ARC/INFO, ArcView, ARCNetwork, Spatial Analyst, MapObjects LT, GRASS, IDRISI, MapInfo, TransCAD)
• Database packages (e.g. dBase, Access, Paradox); • Decision analysis and optimization software (e.g. LINDO,
EXPERT CHOICE, LOGICAL DECISION); • Statistical and geostatistical software (e.g. S-PLUS,
SPSS, SAS); • Simulation (e.g. Spatial Modeling Environment)
Specific DSS• Systems devoted to the analysis of a particular
set of decision problems• Support decision makers in tackling semi-
structured problems• Active Response Geographic Information
System• IDRISI Decision Support• GeoMed• Spatial Group Choice• winR+GIS Spatial Decision Support• CommunityVis
50 years of decision-making
• 1957 NRC report recommended burying the waste in a permanent repository
• Need a “safe” site for 77,000 tons of highly radioactive waste
• Safe means stable for at least 10,000 years as measured by radionuclides in surface and ground water downstream
• Need a stable place, free from hazards• Storage-movement-disposal issues• No solution in spite of 1982 act (DOE by 1998).• Single site eventually chosen
Yucca Mountain Waste Repository
What is the radionuclide travel time from the repository to the water table?
Question addressed through modeling
• Conceptual model selection
• Calibration• Predictions
UZ Travel Time Predictions: 1995-2003
Effective Continuum
• Fractures and matrix assumed to be in pressure equilibrium
• Calibration yielded water perc. rates of 0.01 to 0.1 mm/y, dry fractures
• Travel times to water table of about 350,000 years
Dual Permeability• Fractures can flow even
when matrix is unsaturated
• Calibration could be attained with more reasonable perc. rates of 5 mm/y
• Travel times to water table of 10’s to 100’s of years possible!
Early models Current modelsData collection, revised conceptual model, computational model advances
Conceptual model uncertainty is critical to assessment of overall system uncertainty
Cl-36 Observations Confirm Rapid Transport Pathways
100
1000
10000
0 1000 2000 3000 4000 5000 6000 7000 8000
ESF Distance (m)M
ea
su
red
36 C
l/C
l (x
10-1
5)
Bomb-Pulse~ Bomb-Pulse
BackgroundFaults
100
1000
10000
0 1000 2000 3000 4000 5000 6000 7000 8000
ESF Distance (m)M
ea
su
red
36 C
l/C
l (x
10-1
5)
Bomb-Pulse~ Bomb-Pulse
BackgroundFaults
Atmospheric fallout from nuclear weapons testing (1950’s and 1960’s) is present in fluid 200-300 m below ground surface. Fault zones appear to be the pathway.
Source: Fabryka-Martin et al., 1997, YMP Milestone SP2224M3
Key Attributes of Repository Safety Strategy
Limited Water Contacting Waste Package
Long Waste Package Lifetime
Slow Release From Waste Package
Low Concentration of Radionuclides in Groundwater
Tpt
ClimatePrecipitation
UnsaturatedZone Flow
Infiltration
1
2
3
Tcp
Tcp
GDF
Tcp
From
Mountain Crest
to Repository
~ 1,000 feet
Drift Cross Section
Waste Form Degradation
Radionuclide Mobilization Through Engineered Barrier System Transport
Thermal Hydrology Drift Scale
Near-Field Geo-chemical Environment
Unsaturated Zone Flow
Seepage
Waste Package Degradation
4
5
6
Saturated Zone Flow
andTransport
Unsaturated Zone Flow
and Transport
TcpTcp
~ 20 kmAmargosa Valley
Water Well Pathway
Saturated Zone WATER TABLE
9
Biosphere
Water
Plants
Animals
People
7
8
From
Repository
to Water Table
~ 1,000 feet
The Yucca Mountain Decision Model Framework
Many unknowns
• Will there be new faults and fractures in the next 100,000 years?
• Will the local tectonics remain inactive?
• Who will be there to notice in 12,005AD?
• What language do you write the warning notice in?
• [etc]
Current YMP Total System Model “Overview”
Can such a model be “understood” by anyone besides the developer?
Problem N: Controversy
DOE Admits Yucca Mt. Safety Information May Have Been Lied AboutMarch 17, 2005, 04:25 PM It's being called a devastating blow to the Yucca Mountain Project -- some of the government's scientific data may have been faked. Workers on the proposed nuclear waste dump are under investigation for lying about their research -- meaning the "sound science" President Bush said he was following might be wrong
Summary
• SDSS has been defined as an interactive, computer-based system designed to support a user or group of users in achieving a higher effectiveness of decision making while solving a semi-structured spatial decision problem
• The SDSS concept is based on the DDM (dialog, data, model) paradigm; a well-design SDSS should have balance among the three capabilities.
• There are three sets of technologies for building an SDSS: the DSS development tools, the DSS generators, and specific SDSS
• The DSS tools facilite the development of specific SDSS or they can be configured into a DSS generator which in turn can be used to build a variety of specific SDSS.