Title: Environmental Data Modeling: REDM, DREDM, Ontology and Metrics
1Environmental Data ModelingREDM, DREDM,
Ontology and Metrics
- Dale D. Miller, Ph.D.
- Annette Janett
- Melissa Nakanishi
- Lockheed Martin Information Systems
- Advanced Simulation Center
- Bellevue, WA
2The System-of-SystemsInteroperability Problem
- Providers of Data
- Whether observed/measured, interpolated, or
generated/modeled - Willie Sutton Rule
- NIMA, AFCCC, FNMOC INE ARP
- Question What do you want and how should it be
represented? - Developers of Systems/Software
- Interact with (use) Data
- C4ISR, MS, Games,
- CECOM, STRICOM, ESC, PMS430
- Question I need this, it will be represented
like that, and you have what!? - Specifiers of Functionality
- Define behavior/capability required (supported by
Data) - TRADOC, NSC, Schools, Consumers,
- Question When will I get what I want, and how
good will it be?
3The Bottom Line
- Goal Establish common EDMs across communities
of interest - Increased interoperability (pre-ex and runtime)
- Increased data reuse and decreased data
manipulation - Increased data availability (pooling of
production resources) - Method
- Capture existing EDMs of providers,
consumers,and system-level requirements - Develop common EDMs as rational supersets across
appropriate sets of providers/consumers/systems - Will require negotiation and adjustments of
individual EDMs - Establish result(s) as reference EDMs
- Characterize specific provider/consumer/system
EDMs as profiles of those reference EDMs - Objective is a single reference EDM across the
broadest community base e.g., a Reference EDM
for Terrain
4Why Data Models
- Benefits of Environmental Data Models (EDMs)
- Interoperability EDMs allow you to compare and
contrast similar or diverse simulations to
evaluate interoperability. Use of EDMs early in
the system development process can help in the
development of an interoperable solution - Requirements EDMs can be used to specify and
document system data requirements. EDMs can be
used to identify source data meeting the needs of
the system. - Analysis EDMs enable you to analyze the models
used within a simulation, identify models that
may be plugged in. EDMs provide to behavior
developers, the data available to the developer. - Benefits depend on
- Common data dictionary, EDCS
- Common data model framework, CDMF
5C4I/MS Interoperability
An Interoperable MS and C4ISR Framework
D. Timian et al., Report Out of the C4I Study
Group 00F-SIW-005
6Solution - Common Data Model Framework (CDMF)
- Extensions to classical E-R modeling
- Framework for data modeling
- Expressed in a language, contained in a
relational database - May be directly queried
- Diagrams may be derived from the language
- Logical Data Model
- Feature (Entity) Environmental objects having
common attributes of interest - Attribute A characteristic or property
associated with an entity - Relationship Specific or non-specific
association between entities - Attribute Values
- The set of allowed data values that an attribute
may take on - Enumerant, Textual, Numeric, Interval
7Features, Attributes, Relationships
- Feature
- Classification
- Type (point, line, area, grid)
- Variant (for variations such as different
coverages) - Attribute
- Feature code as indicated above
- Attribute
- Relationships
- Facilitate reasoning
- Levels of resolution (aggregate)
- Connectivity (over, under, connected to)
8Data Dictionary EDCS
- Classifications, attributes, enumerants, units of
measure - ISO/IEC Final Committee Draft (ISO/IEC 18025)
- EDCS extensions
- Labels vs Codes
- Qualified attributes
9Environmental Data Models (EDMs)
10Common Data Model Framework (CDMF)
Setup
Environmental Data Model (EDM)
Capabilities
Maintenance
Comparison
Conversion
Diagrams
Verification
Mapping
Using MS Access MS Visual Basic
11Reference/Requirements EDMs
- EDMs have been or are being developed for many
MS and C4ISR systems - Reference EDM (REDM) will be the intersection
of their contents - Defines maximal environmental content for which
all systems can interoperate - Goal is to have the Reference EDM as large as
possible - Data Requirements EDM (DREDM) will be the union
of EDM contents - Defines a minimal set of environmental data for
which requirements have been established
12DREDM / REDM of Stakeholder EDMs (Terrain)
13Comparing Feature IDs
- 1 feature is common across 8 EDMs
- 4 features are common across 7 EDMs
- 12 features are common across 6 EDMs
- 692 features appear in only 1 EDM
- 1893 features in total
14Syntax vs. Semantics
- Well established that similar semantic can be
expressed via multiple syntaxes (even in EDCS) - E.g., LIGHTHOUSE feature vs. BUILDING feature
with BUILDING FUNCTION LIGHTHOUSE - Generalize Specialize relationships
- If one EDM has a TERRAIN_OBSTACLE and another has
LOG_OBSTACLE, they share some semantic similarity - Attributes are important too if, in the first
EDM, TERRAIN_OBSTACLE has an attribute of
TERRAIN_OBSTACLE_TYPE with an allowable value of
LOG_CRIB, the semantic is closer yet
15Fuzzy Comparisons
- Equivalence Classes
- An Ontology for the EDCS
16Equivalence Classes
- Feature of high specificity (Generic feature
with specific attribute) - LIGHTHOUSE (BUILDING, BF LIGHTHOUSE)
- Currently identified over 650 equivalences
17Some Equivalences Better Then Others
- Maintained a Confidence Level field
- Inexact matches
18An Ontology for the EDCS
- Relationships
- Hierarchical A ltWIRE_OBSTACLEgt is a
ltTERRAIN_OBSTACLEgt - Component ltAPRONgt is a component of ltAERODROMEgt
- First cut relate features when the EDCS label
of one appears in the definition of the other - WIRE_OBSTACLE A ltTERRAIN_OBSTACLEgt constructed
of ltWIREgt, usually containing barbs or razors a
wire obstacle.
19Ontology Refinement
20Barriers
21EDCS Extensions
- In the EDCS, a group of related concepts often
does not have a parent which embodies this group - New EDCS classifications proposed for completeness
22TERRAIN OBSTACLE group
23ABATIS group
24VEHICLE BARRIER group
25Results of Applying the Ontology and Equivalence
Classes to the 10 Source EDMs
26New REDM Approach Common Core Data Model
- TLM / VMAP2 as starting point
- Represents what todays warfighters are demanding
- Surrogate for C4ISR
- Adding terrain overlays for dynamic environmental
data elements from MIL-STD-2525B - Intersect with WARSIM TCDM and OOS EDM-Terrain
- The two emerging Army MS systems
- Grow this intersection with the ontology analysis
and equivalence classes
27Feature and Attribute Counts
28Fuzzy Intersection Methodology
29Common Core Data Model (CCDM)TLM/VMAP2 2525B,
WARSIM, OOS
30(No Transcript)
31Measuring the Alignment between EDMs
- An extension to the work of Brian Haugh (IDA) et
al. in measuring the alignment between the
LC2IEDM and TCDM - Which have different data dictionaries
- What percentage of concepts in data model A
align with concepts in data model B? and vice
versa - alignment from A to B is A n B / A (A n
B) - alignment from B to A is A n B / B (A n
B)
32Haugh et al. Methodology
- Drill down may terminate prematurely if alignment
is zero - Alignments are rolled up from the bottom up
- Computed alignment between two data models is
primarily driven by alignment of attribute values - Assigned alignments while drilling down are
discarded
- Drill down to make alignment assessments at four
levels - Assessments most subjective at the conceptual
level, most rigorous at the enumeration level
Conceptual
Entire Data Model
Entities
Feature by Feature
State
Values
Attribute by Attribute
Value by Value
33Alignment (cont.)
- Types of attributes
- mensuration attributes, which are generally
continuous-valued measurements of a property of
an entity HEIGHT, LENGH, WIDTH, SOIL MOISTURE,
TEMPERATURE, etc. - qualifying attributes, which add additional
descriptive information about the entity, but do
not change its fundamental thing-ness.
Examples include COLOR, SURFACE ROUGHNESS, SOIL
TYPE, GENERAL DAMAGE FRACTION, MATERIAL
COMPOSITION, etc. - metadata attributes, which include UNIQUE
IDENTIFICATION NUMBER, SOURCE TYPE CATEGORY, etc.
- identifying attributes, which serve to further
clarify the type of object the entity represents.
These are generally enumerated, and include
BUILDING FUNCTION, OBSTACLE TYPE CATEGORY,
BUILDING COMPONENT TYPE, etc.
34Alignment (cont.)
- Reduced entities in a data model
- (entity type, identifying attribute enumeration
value) - Capture the following metrics
- Assigned alignment of reduced entities (based on
analysis of definitions) - Assigned alignment of mensuration and qualifying
attributes on a per-reduced-entity basis (based
on analysis of definitions) - Assigned alignment of metadata attributes on a
per-reduced-entity basis - Calculated alignment of non-metadata attribute
values on a per-reduced-entity basis - Calculated alignment of metadata attribute values
for mensuration, qualifying and metadata
attributes - Averages in each class of metrics
- But maintain as six separate metrics
35Conclusions
- Reasonable REDMs for a set of EDMs cannot be
generated syntactically - Equivalence classes and EDCS ontology allow
semantic comparisons - New metrics have been proposed for measuring the
alignment between two EDMs, even using different
data dictionaries - Going forward
- Many judgment calls in defining ontological
relationships - Needs review by larger community