The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008
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polygon will help form the corresponding relationship between
components and form simple volume automatically.
3.3 Conceptual model of OO-Solid Model
Conceptual model is abstract concept sets of relations among
entities; it is the semantic interpretation of geographical data
and is the most senior abstract. It easily converts into a logical
model and is independent of the specific computer achieved.
Component includes six primitives: node, arc, polygon, region,
component-face, and component, which constitute the basic
elements of data model. In geological mining areas, nodes can
describe the point geological target, such as ore sampling point,
gas gathering point etc. Arcs can describe line objects such as
borehole line track, folding hub, broken coal intersecting lines
etc. Regions can describe surface objects, such as the formation
level, fault plane etc. The simple volume can be composed by
components with some of same attribute, and the complexity is
composed volume by the simple volume, furthermore, the
composites volume is converged by the simple volume and the
complex volume. Space objects are designed into different
object classes, and the superior class is generalized such as
geological object class. On the basis of above model, the
conceptual model of geological object of OO-Solid model is
redesigned (figure 2).
Figure 2 Conceptual model of OO-Solid Model for Geo-Objects
3.4 Logical model design of OO-Solid Model
Conceptual model clearly described the level of relations
between the objects and its constituent relations. In order to
facilitate the management of object data model and further meet
spatial analysis, visualization, the corresponding logical model
is designed. Logic model is a mathematical description of the
concept of model. Logical data model is the concept of data
model, data entity (or records) and the relationship between
each other; it is the logical expression of geographic data, and
the middle layer. The user can see the geographical space of real
world. According to the concept model, the layer between the
geological targets and geometric elements can be pushed: Any
geological objects can be polymerized by the components. The
components are polymerized by the component-face. The
component-face joint from the polygon, Polygon is composed
of a number of arcs. Arc is composed of many nodes. Any point
in a three-dimensional space corresponds to a unique 3D spatial
coordinates(x, y, z), which is located the point of spatial
location. Because the primitives and conceptual model of
OO-Solid model are modified through redesign, and logical
model must be redesigned. According to the modified primitives
and conceptual model, the logical model is redefined (Figure 3).
Figure 3 Logical model of OO-Solid Model