5. Discussions
As described in Sections 3 and 4, the different types and categories of
knowledge tend to coexist, except definitional knowledge. Knowledge
representation can be performed using knowledge-type-aware concept
mapping, wherein the types and categories of knowledge play a vital
role. It is worth mentioning that when a concept map represents a piece
of knowledge claim, it may incorporate other relevant contents, such as
those relevant to knowledge provenance. At the same time, other
non-knowledge contents (e.g., information to help users grasp the
meaning of the concept map) may also be considered part of a concept
map. To understand this issue in greater detail, a creative design
process has been considered and represented by a concept map of a
solid-fuel-based engine developed for Mars exploration (Shafirovich and
Goldshleger, 1992; Shafirovich et al., 1993; Hatchuel and Weil, 2008;
Ullah et al., 2012).
Figure 9 depicts seven interdependent concept maps, denoted by
C1,…,C7, which collectively represent the conceptual design of
the solid-fuel-based engine. For the sake of analysis, internal
combustion (IC) engines are considered to be available in the market a
priori. The same, however, is not true for solid-fuel-based engines.
Consider the concept map (C1), which boils down to the proposition that
operation of an IC engine requires a fuel and an oxidizer. This is the
definition of an IC engine, and therefore, represents a piece of
definitional (or analytic a priori) knowledge. The second concept map
(C2) boils down to the proposition that the earth’s atmosphere supplies
ample O2 (> 20%) and hydrocarbons, but
hardly supplies any CO2 (< 0.05%). This is a
piece of informal-induction-based knowledge. Experimental data regarding
chemical analyses of substances found in the earth’s atmosphere form the
knowledge provenance for this piece of knowledge. The third concept map
(C3) boils down to the statement that an IC engine uses
O2 as an oxidizer and hydrocarbons as fuel. This
qualifies as informal-induction-based knowledge, and data regarding
oxidizers and fuels used in existing IC engines form the provenance for
this piece of knowledge. Concept map (C4) boils down to the statement
that an ample supply of fuel and oxidizer is essential for an IC engine.
This, too, qualifies as a piece of informal-induction-based knowledge
for which data concerning the performance of existing IC engine
constitutes knowledge provenance. Up to C4, the design process deals
with existing IC engine. From C5 onwards, the focus is shifted to a new
engine using Magnesium (Mg) as solid fuel. The fifth concept map (C5)
boils down to the proposition that the engine for Mars exploration may
require fuel and an oxidizer. This is an analytic-a-priori-based
creative knowledge. Since there exists no knowledge provenance (data or
theoretical analysis) available to support this proposition; it is
neither true nor false at the time of its conception. The sixth concept
map (C6) boils down to the statement that Mars’ atmosphere supplies
ample Mg, CO2 (> 95%), hardly supplies any
O2 (< 0.1%), and does not supply
hydrocarbons. This is a piece of informal-induction-based knowledge, and
experimental data obtained from chemical analyses of substances found
within Mars’ atmosphere form the provenance for this knowledge. The last
concept map (C7) boils down to the proposition that an engine for Mars
exploration may use Mg as a fuel and CO2 as an oxidizer.
This represents analytic-a-priori-based creative knowledge, since there
exists no knowledge provenance (data or theoretical analysis) available
to support this proposition at the time of its inception. Thus, it is
neither true nor false. This piece of knowledge, in turn, leads the
design process of solid-fuel-based engines for Mars’ exploration into
the embodiment, parametric, and detailed design stages, respectively.